Any social media website and there are many of them including this one. It's all FREE too. Just start dialogs around, and about the item. If you pay attention there are quite a few people promoting products on ANSWERS every day.
Actual networking! I'm not talking about social networking sites - but going out and meeting people who are interested in your product the old fashioned way! Find groups of people that you can market to, special interest groups, local Chamber of Commerce, fairs, markets, swap meets, etc. Also, direct mail can be a great way to target a market. First, think of who your ideal client is, then develop a couple of ways to reach out directly and get to know those clients so that learn about your product. You can also look into distribution of your product through Amazon or other sources, they can help you advertise and generate sales. Good luck!
it depends what kind of products you want to promote. you could possibly visit forum sites that are related to your products and post a link on the message boards. or you could use facebook. unfortunately, neither of these are great options but it might be better than nothing. better yet, just start a blog.
using social media service you can promote
You can advertise on classified sites, viral marketing sites, safelists and freeadboards. These are great ways to get the word out about your products or services. It doesn't require you to have a website.
Twitter and Facebook tell your friends ar school or family and make magazines
How can I promote products without having a website or a blog?