I hear you on bikes, though buying off craigslist isn't a bad thing to do. The important thing is to get properly fitted on your bike whichever it is, and a close second of course is the right size bike but this is second after a proper fitting.
Any proper professional bike shop, (I think there's revolution cycles and capitol hill cycles for two in DC) has someone on staff who can do this. But make sure the person doing it knows what they're doing. If they have a USCF coach license or have experience as an elite cyclist/currently licensed cat 1/2, they can do this.
Sorry you had to move to DC... Fai de bèn a Bertrand, te lou rendra en cagant
By the way, for the record, I like DC! I'd never been before flying in from Paris, and I expected to hate it. Maybe it's just the cool crowd I've fallen in with, my fun neighborhood, or the great organization I work for, but it's really not so bad.
