Do I need a venders license to sell hand made crafts at a Farmer's market?

I am selling hand made cards and jewerly.

Depends on your local community's laws. If your state collects a sales tax, you may need a sales tax collection license. In both cases, if these are required, they usually posted at the vendor's stall. So, go look around at the Farmer's Market. If you don't see any posted at other craft stalls, you don't need them.