Below is the list of documents needed for H1B Stamping:
1. Employement verification letter
2. Original 797 A
3. Attested I-129 copy
4. Copy of LCA
5. Bank Statement (3-6 months)
6. Pay slips (latest 3-4 slips)
7. All I-20s (including CPT and OPT)
8. OPT card
And kick out the nervousness and welcome the confidence. You will be fine.
BTW: I have H1B stamping date on 3rd week of January 2014. Best of Luck!!!