Another useful webtool for linkbuilding analysis:  Linkdiagnosis.
Easily see backlinks from your competitors
This tool can show you all the important information about your competitor’s links. The report includes pagerank, anchor texts, no-follow information and more.

Linkdiagnosis

Another webtool to check on your backlinks.
Type URL of your website to get complete detailed
information about quality and quantity of backlinks pointing [...]

This easy to use webtool gives you an analysis of the links pointing to your URL or your domain. You can also this to spy on your competitors website and see where he get’s his links from..
Go to Free Backlink Checker

This free to use webtool is very usefull when you want to find potential linkpartners for your website. You just enter your keyword (for instance ‘test’) and the tool will give you the following results (with hyperlinks):
Add/Submit
test “add url”
test “add site”
test “add website”
test “add your site”
test “add a url”
test “add * url”
test “add * site”
test [...]

CommentKahuna is a free linkbuilding tool using blog comments.
It searches related blogs relevant to your keyword. With your profile prepared you can easily post comments and do your linkbuilding. Since most blog comments are moderated, you want to make sure that you comment is usefull. This way you can make nice relavant one-way-links. You can [...]