Yahoo! site explorer offers you the ability to find vital information about a website like you get information about the pages indexed, incoming links, and popular pages, just enter the URL of the website in the search box and hit, you will get review back links pointing to specific pages and the most popular pages from any site and find pages that link to specific site or any page.

Also using this tools, you can see where other sites are getting their links from & why they are ranking higher than you. The other feature include authentication via META tags and more detailed authentication errors and it also let you easily remove URLs from Yahoo’s Search index that you wont like to link with. You can also use this tools locally through their API, for more information about this local features check on the site explorer API:
yahoo site explorer