Ok, this is a fairly complicated and very very 'open source' part of Apache. I say this, because open source software can often be over-complicated yet very fast and powerful and that is exactly what has happened to mod_rewrite.

I've never actually use this before, so I won't try and help you from expereience...instead...
Here is the official documentation:
http://httpd.apache.org/docs/mod/mod_rewrite.html

And they also have an URL rewriting guide:
http://httpd.apache.org/docs/misc/rewriteguide.html

But most useful of all may well be this tool:
http://www.webmaster-toolkit.com/mod...enerator.shtml
which lets you input an original url and the url you want and it provides you with a rewrite rule :wink:

I hope this helps!