Branford Bikes if you are in to campy stuff, though they carry lots of Shimano stuff as well. They even carry replacement parts for the insides of campy brifters and for $5, they will sell you instructions on how to take campy brifters apart.
Ever since Nashbar got bought out by Performance, I can find nothing good to buy there. It used to be that you could find somewhat obsoleted parts there for good prices, and they had lots of stock at all levels of quality to choose from, from both Shimano and Campy. Now, all they offer is the standard stuff that everyone else (particularly performance bike) carries, at full retail price and with very limited choices. I can find no point in shopping there anymore. They are also "Shimano Authorized" which is a code word for "Shimano Restricted", so it is getting more and more rare to find anything Campy, particularly at the value level lower than Chorus. They are so much like Performance Bike now in what they offer that I wouldn't be surprised to see Nashbar go the way of SuperGo. Probably the only reason they keep the Nashbar site around is that there are some people who are partial to the Nashbar name.
Harris Cyclery is a great place to find parts which are not so race oriented. They carry chainrings of all sizes, generator and multi-speed hubs, fixed gear parts, and other stuff which the major catelogues don't carry.
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Cat 2 Track, Cat 3 Road.
"If you’re new enough [to racing] that you would ask such question, then i would hazard a guess that if you just made up a workout that sounded hard to do, and did it, you’d probably get faster." --
the tiniest sprinter