For me, the best is a relevant forum and also a link exchange. The traffic from social bookmarking will stop in any moment, cuz it is actual now, but after some days, it wouldn't be in the home page.. YouTube is a great way too
I think the best place is search engines. Other methods such as forum posting and social bookmarks also helps.
For free: Build your links via some High PR social bookmarks (like digg, kaboodle, properller, delicious, stumbleupon,) Submit your product-related articles to the Internet (like blogger,press and so on) ....
I think we can get more traffic from craiglist ad posting; press releases, articles and forums are also will give you more traffic. Thanks
I won't consider anything better than forums. Its the best way to receive traffic and get good exposure.
You can get a lot of traffic from the social bookmarking sites. However, I don't think the quality is very good. Most of those people will click on anything, not even being interested they just click your link. Twitter folks do this a lot. I think search engine traffic is better quality as if they visit your site through google search they are actually looking for your info to begin with. But you never know social bookmarking sites are free, so why not I guess.