>Cross Training>Buying a Bike for my first Tri
I agree with what most people have said about buying a used road bike. It's what I did. You don't want to ride a tri bike first thing. Really. It will hurt, and it will be hard to control.
I disagree on one minor point though: don't put aero bars on a road bike. Aero bars pull you forward into an aerodynamic position that is great for tris, but if the bike fits you in aero position, it won't fit you in road position (and vice versa). You'll be more aerodynamic, but your back will be getting stretched weirdly, and you probably won't be able to generate as much power for very long.
A tri bike is shaped differently from a road bike in tons of little ways. If/when you want a tri bike with aero bars, get that. Until then, if the road bike fits you it won't be hurting your time more than a minute or two.
Obviously IMO. At the very least, make sure that there's a generous return policy on the aero bars and time yourself a lot before and after putting them on.