seriously, i grew up in harrisburg (i've since moved) and upon return visits to see the folks, i always venture 'round town to see if anything has changed. not much of a tri scene there and if i recall correctly, tri speed was, in fact, the closest tri shop around. there is a quite friendly and knowledgeable group of roadies over at bushey's in new cumberland if it's bike expertise you seek, but i'm not too sure they speak 'triathlese'.
maybe someone else on this forum is in the know, but i'm doubtful you'll find something in the 'burg.
edit: if you're going to drive 1.5 hours anyway, you may want to investigate tri shops in philly.