Welcome to the neighborhood.

I don't know about messenger work, but you might check out eleventooth.com, which is the local messenger site.

As for shops, you might try:
Salvagetti @ 1234 speer (really nice staff, very good shop)
Turin @ 700 broadway (kind of elitist, but a decent shop)
Cycle Analyst @ 700 S pearl st. (knowledgeable folks, lots of obscure used parts)

These are all very close and easy to get to.