Darren Rowse has a lot of good tips on how to find readers to your blog.
1. It takes time
2. Quality Content and Good Design (Also try to keep your content up to date and topical)
3. Link to others
4. Comment on others blog
5. Interact with Readers
6. Update frequently
7. Search engines
8. Add a signature to your outgoing email
9. Web Rings
10. Add an RSS feed to your blog
11. List your site on Portals
12. Blog Search Engines and Indexes
13. Get Involved in others Blog Projects
14. Get involved in other web forums
15. Take all advice with a grain of salt – Be yourself and have fun!