Promote yourselves locally, and create all the positive word of mouth you can. Some ideas I've seen used in my area:
Doing site designs free for local non-profits, with the condition that your name is mentioned whenever they promote their own website. (Visit us on the web at www.nonprofit.org, site deisgn by YourCompany)
Join the local Chamber of Commerce.
Donating services to charity auctions and sponsoring popular community events.
Get a YellowPages ad!
Don't for a moment expect to get significant business from "designed by" links on your client's pages. It's all about word of mouth at the start.