1. 24-7PressRelease.com – Free release distribution
2. ClickPress.com – Distributes to Google News and Topix.net.
3. Express-Press-Release.com – Free release distribution
4. Free-Press-Release.com – press release distribution for free
5. Free-Press-Release-Center.info – Distributes release, plus web page and keyword link.
6. TheOpenPress.com –Free distribution for plain formatted releases.
7. PR.com – distribute your press releases with login and company profile.
8. PRBuzz.com – Free distribution to search engines, news sites, and blogs.
9. Press-Base.com – Submit release for free with front page promotion
10. PRLeap.com – Free distribution to newswires, search engines, and RSS feeds.
The last tip I will leave you with is make sure you write quality press releases and follow best practices. If you are unfamiliar with press release formats many of the sites above have resources and sample press releases for free.