how do I search urls instead of site content?

[shine]

I know there is a way to make search engines look for your item in URL's instead of in site content and metatags, but I can't think what it is! Help?

[moswell]

If you use Altavista to search a URL you just type URL:blah Where Blah is the bit of the URL you want to search for, eg. URL:www this method does also search the sub-directories of a website for the search criteria