Jen, have you checked out Old City yet? Clubs, bars, bands, food...sorta the hip spot of Philly. Here's a club guide I googled which could be of help...don't worry you will meet people in no time......http://philadelphia.citysearch.com/roundup/38266/philadelphia/.html
Sadly I can't personally recommend which spots are the best but you can scan the reviews and part of the fun is exploring yourself as well....
Sadly I can't personally recommend which spots are the best but you can scan the reviews and part of the fun is exploring yourself as well....