How do I make a program, or download one, for a RPG based website so I can use experience points to buy skills?

I need a program that acts like a typical store, where as a member of my site it keeps track of your experience points and uses them like money to buy skills and spells. Also, I need a similar program to do the same with member gold to buy equipment. Please note that none of this is real money, just for the RPG fantasy experience. Thanks to all who can help me on this endeavor.