I think a good website will be dollar for dollar the best way to bring in new customers that you can find.
My case is probably a little different than yours is since the contractor part of my business depends almost totally on new customers. Basically the only thing I do is hydroseeding and it is pretty much a one time thing. When I added my website, my business more than doubled. I rank very high on Google but don't get a lot of traffic. I do get more than a 50% conversion rate. In other words about half the guys who visit my site call for a quote and I get the job from about 80% of those who call.
I have a simple 5 page web site that I did myself. The cost was almost nothing. Everyone who wants to grow their business should have a web site.