I locked my $280 Motobecane Track up on campus today, and when i came back from my class there was a Fuji Track Classic ($550 retail) next to mine. I swear it's the exact same bike except for the colors. The Motobecane Track is a great bike for $280, but you'll probably have to spend a little bit more to change the gearing and pedals out on it, and also to get a lock ring tool. With good pedals/cages a new cog, and what not you'd probably only spend $350 with everything.

If you were going to spend more than that and maybe piece together a bike the Leader frames are awesome looking I thinking and not super expensive.