Congrats! Oakland and Shadyside are the standard college haunts, but pretty much anywhere in the East End is easily doable by bike - Lawrenceville, Friendship, Bloomfield are all good options also (Bloomfield is pretty close to university city prior to the gentrification). If you're looking for a roommate or more info, take a look at board.nevertellmetheodds.org - messageboard that deals with most things pgh.