Hello, and welcome to the Pennsylvania Chapter. You too can become a member of the chapter simply by going to the Pennsylvania Sign Up thread and requesting membership.
When you want to post about parts or buying, selling, trading, swapping or giving away stuff, put it in the thread so titled.
I personally don't know of any stores in the Harrisburg area but you can contact DiscountPowerPrt. He's a sponsor and supporter of FTE and also a member of the Pennsylvania Chapter who deals in parts, as his name states.