I agree with the other 2 posts in that some people will go all out and get the $8000 titanium, pro team bike whereas others will get the $200 off of craigslist. In some sense it's what your budget allows. Both are fine paths.

However, I think you are sorta asking what a decent median path not the crazy extreme path..

I'm not sure of pricing these days but a brand new "decent" road bike will likely cost you about $1k-2.5k. Decent is assuming 105 level components. YOu might be able to find some last season bikes on sale and it might be a bit lower

In this market, you can also get a nice used road bike for under 1k if you don't mind a few miles on it. For bang for your buck, a used road bike is a better deal but *only* if you know what you're looking for as far as sizing, materials, quality, and the general "how used is it" type of stuff.

The 1k-2k range is probably a good range to stay in for a first road bike for most folks until they get some miles under them and then decide who they are as a cyclist (cross, roadie, touring, commuter, etc). Then like most of you'll end up either upgrading to a different bike w/ better frame n better components or buying a different bike for a different adventure

Go test ride bikes, all sorts of bikes and you'll also start to figure out some of this too.

Hope that helps.