I do web graphic work as a side business and this is my favorite answer to your question...
"so you want a want a new car"
a new car you ask...??
"yeah, a new car --
cause the cost of your site will be directly proportianate to what you want to do with it -- what kinda options do you want, what do you want it to do, do you want it to be fast, do you want it to be a sports car, a luxury car, a compact, or an suv; do you want 4 wheel drive, front wheel drive, blue, red, silver, a V8, automatic, stick, etc...
Your sites cost will be directly proportianate to what you want to spend. For a simple no frills site look at spending maybe $50-150 per page, and it goes up from there.