• Visitor's passport
• Form I-134 with notary signature. Get this "Affidavit of Support" form from here
• "Credit statement" from your main bank account. It's better to have some good bank balance (may be more $5,000 or so should be ok)
• Letter from your employer on company letter head, stating that you'll be employed for the next 1 year with them, with a minimum annual pay of .....
  A couple of recent pay stubs might be helpful.
• Copy of your H-1B/L1/whatever visa. If it's H-1B, copy of its approval form (I-797)
• Copy of your recent tax returns, if there are any
• An invitation letter to the person(s) you are inviting to US.
  In that, you've to mention that you can take care of all their needs including tickets
• A letter to the US consulate in Chennai/whatever, India, requesting for a visitor visa to the visiting person, mentioning that you can take care of their every need, including their tickets

NOTE: Check the info in the visa stamped like (passport number, full name, consultant name, etc)
NOTE: Since I've never got this stuff done, not very much sure about the contents.