Your best bets are to check with hobby shops in your area. They are normally familiar with any clubs and members who frequent their shops.
IPMS has a number of chapters in PA. They are located in Erie, Mechanicsburg, Pittston, Philly, Scranton/Carbondale, Sharon, Whitehall, and Willow.
http://www.ipmsusa.org/Groups_Contests/state_select2.asp?ST=PA
If you are close to the state line, you can also check for chapters in adjoining states.
Beyond these options, other members may have additional information...
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