Take a look at Kish Bikes and Kirk Bikes. They both build Ti bikes. Kish is a little less expensive.
Here is a link to their pricing:
http://www.kishbike.com/prices.htm
If you want carbon, take a look at Calfee, Parlee and Crumpton. I think Calfee is less expensive than the other two.
http://www.calfeedesign.com/index.htm