Falcon,
You need a minimum of 25 jumps for an A license. There is a checklist of skills and knowledge you must demonstrate:
http://www.uspa.org/publications/for...Card_09-06.pdf
Depending on how often you can jump, it will probably take something on the order of a couple of months of weekends, and cost around $2000. This is not including the gear you will undoubtedly be buying.