I hear bikeophile.com is good ;)

My experiences with Nashbar/Performance have been quite good. Performance ships quickly and it arrives quickly. Nashbar Ships quickly and takes a while to arrive. The next place I'm going to be ordering from is Supergo.com since they got the super sweet deal on the Aireon Team Race Saddle for under 30 bucks.

For all the little things track specific, I will be ordering from Tony@IRO or John@Business Cyles or Gene@Spicer Cycles. the three of these gentlemen have managed to carve out a niche market for themselves by offering superior service and commitment to their products/knowledge on what you will be needing for your specific application. These three stand head and shoulders above anyone I have ever had the (dis)pleasure of dealing with online.

I'm not knocking any of the other nice track places to buy stuff from, but these guys stand out in my mind. They love what they do and hope to spread some of their happiness and knowledge with their customers. Use them, you won't be dissapointed =)

I have built my entire bike online, so I definintely have to chime in on this one. John at Business is awesome. The guys at Ben's Bicycles were cool too, treat you right (eBay + OBS + LBS). Performance wasnt too hot. Nashbar was alright. JonesBikes on eBay was a good one. Cant really remember anymore at the time, ask.

For anyone in the UK HubJub is an absolute must. They are a very small fixed-gear specific commercial website with customer service that is second to none.

Can't recommend them highly enough.