Let me give some info related to H-1B visa stamping. I don't say it's a must on one's part to know before going there, but u can feel at home by knowing these small things! All these things may be very silly for those who have already seen the consulate but for first time visitors, it'll help, I believe.
The most important thing is, don't get tensed up, as almost there r no rejections in the H-1B visas. They're giving them as long as u've genuine acads and experience.
For all the info about US Consulate, Chennai, just check out this site.

1. Go for stamping on Thursday, preferably.
   The very first thing is, u be careful about the day u attend the interview. On every Monday and Thursday, student visas (F category) r not allowed and so lot of rush will be avoided. U need to stand in the queue from very early hours of the day. So, it's very much suggested to reach Chennai at least by the before night. 'coz of this, there will be more rush on Monday (by saving a leave in the office that lie on Sunday) and so Thursday is preferred.
2. Reserve a ticket back from Chennai on the next day after ur stamping.
   More over, u get ur ticket reserved from Chennai back to here, on the next day evening after the day u go for stamping. If u choose it to be on Thursday, u can enjoy ur stay on the weekend!
3. Stand in the queue by 4am, if it's on Monday, otherwise by 4:30am.
   There will be a very big queue with lot of turns and all that. Don't become panic by seeing its length, they'll allow around 300-400 pple per day.
4. Try NOT to be in the first 50 or at the tail end of the queue.
   There will be a small face to face interview for the 50 candidates in the interview, even if u're supposed to get counter visa. If u r at the tail end, they may stop the pple in the queue after the limit for the day is crossed.
5. Short intro about the movement of queue.
   Around 6'o clock, they'll allow u thru a small gate (only one can enter at a time thru that), after checking whether u've a passport or not. Then once again, they check that passport is with u and they'll give u a small application to fill up.
6. Reg the application form u fill.
   Don't be in a rush to fill it up. U'll have at least 2 hrs to fill that! Most of the questions in that form r very simple, but with very little space provided. So, answer them a bit cautiously. For most of these questions, ur consultant will be giving u a FAQ about these questions and their answers. If u want, u can ask me in person.
   For some junk questions, I'm giving the answers here:
   
   Q.No.31. (a) No (This is something about r u an immigrant?)
   Q.No.31. (b) No ( do )
   Q.No.31. (c) Yes (Do u have LCA?)
   Q.No.34. No for all the bits in this. (These r the questions about were u ever a member of terrorist groups or something like that stuff, I believe none of us can answer "Yes" for any of these :-)
7. DON'T paste the photograph.
   U need one passport size photograph (better to take 2 with u) to stick on the application form. But, the most important thing is, u sign on its back side and then staple it on one corner.
   For this, u better carry a stapler and gum/gluestick along with u.
8. Reg the drafts.
   U need to take 2 drafts, for $45 and $75 in favour of "American Consulate General, Chennai", payable at Chennai. The other thing is, u'll be taking drafts in Indian Rupees only (not USD), that's eqt to that amounts. At present, their dollar price is 46/- and it may be changing. U can find all these details from the above mentioned web site.
   The most important thing here is, u better to take them from some compuetrised bank (where the details will be printed on the draft). They won't accept ur draft(s) even if it's slightly overwritten or scribbled (which happens usually in any bank).
9. Collect ur token.
   After u enter the premises with the application form in ur hand, early birds in the queue can catch chairs in the queue! In that place u've to wait at least till 8:30am. Then all of a sudden lot of pple (around 50) will rush thru the queue to stand before u. Don't get surprised, they're the pple who has got rejected on the before day!
   In that time, from 6am to 8:30am, u need to fill up the application form.
   When u're passing thru the queue, there will be a counter and there u need to give ur $45 draft. That's the entry fee for the US Consulate. They accept this fee, only if u've got a VALID $100 draft. Then they'll give u a token and the receipt for the fee paid.
10. Arrange ur certs in order.
    After collecting ur token, there will be a couple of ladies sitting there to arrange ur certificates in their order. There they won't be asking twice for anything and so be sure to give all ur certificates as soon as they'll ask u. I mean to say, give both ur degree and diploma original certificates and all ur employment/experience certificates.
    After arraning them in order, if u're in the first 50 of the queue, they'll give the bunch to u only and ask u to stand at some counter that is from counter No.2 to 7. Remeber that, only counter No.1 is the cash counter. If u're not in the first 50, they'll collect all ur certificates and ask u to wait in the visa lobby. (All these counters will be there in the visa lobby only).
    It'll be at least 9:30am, by the time u reach visa lobby. This is the only place where u can find toilets and so don't take too much food/drinks, though u can find them in the queue (between 6 to 8:30am).
11. What is a counter visa?
    If u're in first 50, the person sitting in the counter will be checking all ur documents and ask u to pay the fee at "WINDOW 1", otherwise he may ask u for supporting documents. Usually, they'll ask u for all ur marks memos. If u're not in the first 50, u'll be coolly waiting in the lobby and they'll announce ur token number to come to Window #1. Notice that, all Americans call those counters as "Windows"!
    Remember that, all the pple in the WINDOWS will be Americans only. U'll be conversating with them, thru a microphone/speaker attached to the bullet proof glass between u both.
12. Pay the fee.
    Once u get a call to window 1, u go there and give ur $100 draft. They'll give u another receipt.
    The only proof that ur passport and/or other certs r with them is the token slip and the 2 reciepts ($45 and $100).
13. Collecting visa.
    FYI, visa is nothing but a stamp (piece of paper) pasted on ur passport. To collect this, u need to come to Consulate at 3pm. Again there will be a queue, but, u'll be out at the most by 5pm. While u're waiting in the visa lobby, they call token numbers and corresponding window numbers. It'll be very cool, no questions, nothing!
14. The token which u get is of pink color.
    Don't get tensed up when they call up for tokens and observe the word they utter in the beginning of the list of token numbers. I mean to say, there r 3 types of tokens: Drop box tokens (Yellow color), Pink color and green color. These r the types I observed and u may find some other types there.
15. About the local journey.
    The Consulate premises is around 7 to 8km from the Chennai Central station, with an auto fare of around 27/-. U can even negotiate for a lumpsum amount of 35/- for that distance. Never mention that, u need to go to Consulate, he'll ask u for a 100/- simply! Mention that u need to go to Saphire theatre and consulate (which is reknown as US Embassy in Chennai) is exactly opposite to it.
    Other land mark is, it's just before the Anna flyover on Mount Road. Don't try to cross the road just like u run in Hyd! The mobile court may fine u for this, upto 50/-. Always try to find some subway, which will there very nearby.
16. Checklist of docs u need to carry with u
    
    • Passport
    • Two drafts (for $75 and $45, check here for latest update)
    • Offer letter (copy of which is filed along with your docs, at INS)
    • H-1B approval form (I-797, looks in a different color, sent by your future employer)
    • LCA (Labor Condition Application, sent by your future employer)
    • Form I-129 (sent by your future employer)
    • Original degree certificate.
    • Original degree marks memos
    • Original diploma certificate with all the marks memos, if there is any
    • Current and past employment/service/experience certificates
    • All hike letters, etc from the current employer
    • Other certifications (they'll never ask you for these)
    • One passport size photo (preferrably two)
    • Stapler and/or gum
    
    They may ask u for the following also:
    
    • Identity card of present job/employment.
    • Business (visiting) cards.
    • 2 copies of resume.
    • S.S.C. and 10+2 certificates.
17. Check the info in the visa stamped.
    Check the info (passport number, full name, consultant name, etc) on the visa stamped and if there is any problem report it immediately and return ur p'port to them. They'll correct it and return it to u on the next day 2:30pm.
18. Ur dress code matters.
    For guys: It's very much recommended to wear a tie but not a blazer. That too, in that Chennai climate (heavily sweating), don't wear it from 4am. U can wear it, while filling up ur app form (around 7:30am or so).
    For girls: Wear some decent looking dress, cool!