I have a $2000 bike ($2500 in today's money) but I didn't buy it that way. Instead I got a medium expensive new bike with "good bones" and starting upgrading it with components that made it suit me better. High tech parts abound these days, some with unique (and desirable) features. This new stuff can be expensive but if you do the installation yourself you still get good overall value, in my opinion. If you have to have a LBS do the install, it is more costly but that way you do avoid the "oops, gotta do it over" issues. So my advice is buy a quality bike (do the best you can to decide what will suit you) but you might want to modify it so save a little for upgrades.
The Old Peddler