You're on the right track. A press release is THE best free publicity for a business. However, everyone else is correct in that you will reach very few customers with this one.

When I had a retail shop I used prweb.com for a national reach that was picked up by a television station that wanted to do a story on the franchise.

But, I had the greatest success with a press release I wrote myself and sent to two local newspapers. From there several other newspapers picked it up and ran their own stories. All were accompanied by great color photos. This went on for months afterward and I only wrote one press release.

For direction in how to write it I followed the advice in a book by Marcia Yudkin. I have a link to it from my site below (scroll down to advertising/marketing):
http://www.smallbusinessstartup.biz/recommended/