Some ideas for you:
- do a simple search on google for "city niche" and look for business with no website on Google Places
- search for business on your local chamber of commerce
- search on yellowpages, yelp and other online directories

After you build their websites you could easily upsell seo, mobile websites, facebook pages etc.

Hope it helps.

Ryan, this isn't my idea but a fellow Warrior had a post recently about searching Google for "website under construction" + "city" and prospecting from this list.

Obviously the client has paid for the domain and hosting and just needs to get their website up..perhaps you can prospect and provide your services to these type of companies..

banditu gave good advice, but i want to follow up
and ask, WHY, are you looking business with no website?

Do you think it will be easier to sell them, over
some one with an existing website?

If that's what your thinking, its not. its easier to sell to someone who has one
already, but is unhappy with it, or its performance...