Social Networking sites aimed at home business owners and entrepreneurs are perfect for advertising and networking. I use them with great success.
Wowzza!!!
Lets you message 50 of your friends at once. Register, set up your profile, add friends, and send out a marketing message to all of them!
DirectMatches
A good and solid community with a lot of active members. As a new member you will get a lot of message from members who "welcome" you and tell you about their business. Use this a reverse marketing, reply to all your messages with the purpose of letting them know about your website/program.