Actually, it depends a lot on what you want.
The domain name (.com) and the hosting are not really expensive anymore. You can have both for less than 100$ a year.
Now, the website in itself is highly dependent on what you're aiming for. A custom coded website full of bells and whistles can cost you 5 grands easy. If you want something on the cheaper side, you can install (or hire / coerce / seduce someone to do it for you) WordPress. WordPress is free and there are tons of free templates. There are some paid templates too, anywhere from 20 to 250$.
While WordPress is not the only free solution out there, it's the one I prefer (and recommend) for it's versatility. Of course, the downside is that you have to pay for your own hosting.
Hope that helps.