Being somewhat frugal, if not cheap, I have been pleased with the Gommitalia Champion, Gommitalia's entry level tubular. Straight and round in my sampling, no bounce on the rollers. The label on the tire is kind of bright initially, but other than that they look pretty good. They seem to be popular for training with the local Tri folk and therefore are readily available in my neighborhood.
Gommitalia make various grades of tubular which I have not sampled, some are even hand made in Italy I hear.
A www search will dig up more info, reviews and availability I'm sure.
Marcus Coles
London, Ontario, Canada