my website is about $25 per month and it was about $300 to get it set up. I do not get a ton of requests from the site but it is a good promotional tool.
Shop around and you'll find web hosting for $3-5 dollars/mo. My site gets me a great deal of business. If you register your domain with this company or that, they'll sometimes throw in free web hosting or vice versa.
my website was setup by my wife and my cousin so I did'nt have any setup costs. I havn't gotten many jobs from it but I have had alot of people hear about me then go there to get more info. And in this way I have gotten alot of jobs from people who were deciding on who to use. Also alot of people like to contact me though it and get more info there. So I find it very useful although I had originally envisioned more people finding me through it.