Here is a massive list of tools to check your backlinks with.... some are better than others..... don't use them all, don't check every day or multiple times a day, and don't use Google's link:yourURLhere.... =) These are all from my Link building blog (in my signature), so if you like the list, please check out my blog...
http://seopro.com.au/free-seo-tools/link-checker/
http://www.submitedge.com/pr.html
http://rankalert.net/backlink-watch.php
http://www.iwebtool.com/backlink_checker
http://www.smartpagerank.com/pagerank-backlinks.php
http://www.backlinkwatch.com/index.php
http://www.professionallinkbuilding.com ... ation.aspx
http://www.linkdiagnosis.com
http://www.domain-pop.com/
http://www.dnscoop.com/
http://www.w3tool.com/backlink/
http://www.linkvendor.com/seo-tools/dom ... arity.html
http://www.1stsearchenginerankings.com/ ... rity-tool/
http://www.piloun.com/info
http://www.thelinkpop.com/index.php
http://www.pagerankr.com/
http://www.webmaster-toolkit.com/link-p ... cker.shtml
