[CentOS] Cluster fun

I've priced some 1 and 2U Dell servers.  Now, I'd like to perform a price 
comparison of COTS hardware for 1 and 2U servers.  What VAR companies do people 
recommend I check out for putting machines together?   I'm perfectly capable of 
installing and swapping hardware components when/where needed, so on-sight 
support is not needed.

Thanks much.

Scott