Gold's Gym of Winston-Salem has a nice blog going called Winston-Salem-Fitness.com.  They do a great job of covering fitness issues without necessarily shilling their own service. If you're looking for tips and clues for your fitness routines then I'd definitely recommend bookmarking the blog or subscribing to the RSS feed.

Recent posts include:

This is a great example of how to use a blog to promote your business.  Concentrate on showing your expertise, help inform people and allow your reputation to speak for itself.  It's really the same idea of doing a presentation at a conference: don't do a sales pitch because you'll immediately lose your audience.  Simply concentrate on delivering value, clearly identify who you are, and in the end you'll end up with plenty of customers.