1. I-539, as mytwocents put it, if your hu*****and's H1 is pending, choose C and include a copy of his H1 receipt. If his H1 is already approved, choose B and include a copy of his H1 approval notice.
2. Copy of passport pages.
3. Copy of current I-94 and I-797
4 Copy of (not original) marriage certificate.
5. Copy of spouse's H1 approval notice/receipt, whichever applys.
6. Filing fee, $200