If budget is an issue for you then you may try linkdiagnosis and backlinkwatch - these tools are free. It sucks that YahooSiteExplorer has been shut down.. I used to check for links here in the past
It seems as if the search engines are being pushed to reveal less stats about a site, which can be good or bad depending on which side you are on
I also use backlinkwatch and yahoosite explorer. But try to use other back link checker tools like in seocentro and submit express. You can also use majesticseo.
Hi Friend You can check Backlink by this method link:Website Domain or You can download google toolbar
Lots of tools available in net, but i have use generally for backlink in google: Type in google " link:abc.com" and backlink checker.
I use Backlinkwatch.com which is the best to check the backlinks. Yahoo Site Explorer has closed recently which is bad news
Frankly I never used any other tools except yahoo's site explorer, however it seems now I have to find some other software which can get the same or better results. I am checking with SEO-Elite and traffic travis now