I would think the Cannondale Capo frame would be a good start. Or a Van Dessel Drag Strip Courage. Aluminum is usually lighter than Ti. For carbon you'll be looking fairly high end ... think Corima, Look, Cervelo P3 Track if you want a pursuit style. Or go with a Calfee. Ruegamer could certainly build you a very good frame as well. Price is pretty reasonable I think for custom carbon.

edit: also if you must have Ti, Spicer has some.