Backlinks are still more heavily valued by search engines than reciprocal links. The ranking of the site you are linking to also plays a factor for your pagerank. Always aim high, and try to get a link on a site with an equal or better rank.
How do you know who's linking to you?
Find out who is linking to you!
To find out how many inbound links you have, you can use a Backlink Checker. This one in particular will tell you the number of Google results, Yahoo results, and Alexa rank.
My Personal Favorite Backlink Checker...
is Yahoo Site Explorer. You can see everyone that is linking to your site, check internal links and external links. Works much better than Google's Backlink checker.
Other Websites to Check Your Inlinks: See how you are doing in the SERPs!
Search Engine Genie Backlink Checker
100% FREE Backlink Checker.
Online Backlink Checker
This one will not only tell you how many links you have, but where.
Strategies for Driving Traffic
An excellent article from SEOmoz about ways to get more traffic to your website.
And how they determine the "value" of your site
Search engines are complicated, and have convoluted formulas to determine a website's page rank. To find sites on the web, search engines have "web crawlers" to crawl the web through every link it finds. The search engines then apply their algorithm to the site and determine the page rank. Backlinks (or inward links) are always a part of this equation. To search engines, the number and quality of backlinks are an indicator of the importance and popularity of a site.
There are many other factors search engines consider, like the age of the site, URL name, image or filenames on the site, anchor text, and keywords in the content.
Gain a link and some traffic by posting in forums
If you've ever visited a forum, you know that they are an excellent source of information that you can often not find anywhere else. Some also receive a very high amount of traffic and are a huge opportunity for whatever niche your site may fall into. By making an effective signature link for each your posts, you can see an increase in traffic. This traffic is often highly targeted.
Rules for Forums
Upload an avatar if possible so that forum users come to know you by your image that's next to your posts
Make a signature that's appropriate but effective, not out of control, large and obnoxious
Be courteous to other members in forums
Stay on topic and add something relevant to conversations, don't just drop something in to leave your signature
Respond often for the best results!