Is there a proper way to get Web 2.0 sites indexed on Google and Bing, can sitemap be generated for my web 2.0 properties on these kind of websites?
Same way as indexing any other site. Add to Webmaster Tools, submit a sitemap, submit to index. Ping and build links to it from other Web 2's, social networking sites etc etc.
Pinging should work, but I would prefer submitting a sitemap.. Also, Social Media sites can help a lot with indexing (post a link in Facebook, Twitter, G+, etc.), but do NOT spam!