For example, I added the following two lines to search the PHP Function Reference on php.net:
<key>PHP Function Reference</key>
<string>http://us2.php.net/manual-lookup.php?pattern=%s</string>
I have also set it up to use an online spanish dictionary (Tomisimo) and Wikipedia, amongst others. I am using Camino 1.5 and OS X 10.4.10.
[robg adds: I tested this on Camino 1.5, and it worked great. To figure out the URL you need to use, run a search for something simple (ie test) on your favorite site. On the results page, copy the URL into a text editor (for easier manipulation). Replace your search term (test) with %s, and then copy the whole URL and enter it as the string. If you have Xcode installed, the plist can be edited in Property List Editor. If you'd like another GUI editing solution, you might try PlistEdit Pro; otherwise, your favorite pure text editor will work just fine.]

