You may need a little bit more than $2000 for a road/tri bike. My friend has Cervelo Soloist and he says can convert it to a tri bike by getting a different seat post, and adding tri bars of course. I've heard others got this bike too for its easy of conversion. Even so, this bike can cost more than $3500 w/ good components.

Somebody posted about Shimano 105's. They're are OK but won't last as long as Ultegra's.

Anyway, thought I'd share. Best of luck.