There's a pretty good thread on some free stuff you can do. Things like craigslist (works for some not for others) Google places, Facebook page are all free links to your website. Some of those tools like facebook help create "virtual word of mouth".
The one thing that's consistent is different methods work better for different people. For every person who thinks Postcards, door hangers, craigslist, cold calling work there's someone else who says it doesn't work for them.
You can create a free listing for your business on our site ServiceVines.com and click List your services for free.