Nice bike
Treks are great nimble and responsive bikes, I love mine.
Lots of places but to be honest I prefer to support my LBS (just like aquarists on forums all these acronyms
LBS = local bike shop). For the amount invested in my bikes I don't mind paying 10% too much for a new helmet or whatever, in return the guys know my bike and me and what kind of riding I do and I think that's worthwhile.