Quality websites will help you to get backlinks.

Search for high PR sites and try to do guest blogging there. I have had decent results with this.

if you want to increase the back links of the site then you have to find the best pr forum then you can increase the back links and they must have the PR then they gives the pr to your page

Forums for increasing backlinks but blogs and articles to increase trust follow and citation of site.

Do Forum posting and Blog commenting

Do Blog commenting and Forum Posting

forum posting
blog commenting
article submission
social bookmarking

Article Posting, Forum Posting, Blog Commenting & Yahoo answers are best way for increasing quality based backlinks.

Well, some ways to increase backlinks are:
Blog commenting
Guest blogging/ writing
Directory submission
Social bookmarking

But make sure the backlinks you generate, are high quality and relevant to the content you offer.

Forum submission
Guest posting
Directory submission
Search engine submission

I believe social media sites are the number effective way in driving traffic to your website.

I'll prefer Article Posting, Forum Posting, Guest Posting + Blog Commenting for increasing quality based backlinks.

All this tools are effective, but at the moment the most important tool is web content.

Anybody have a list of forums I can join for the real estate niche?

social bookmarking and directory submission are few ways to increase social book marking