Thanks i will have a look at it :)
I'm mainly looking for single player mods, something that add or improve the original if possible.
It's a Q3-engine game. There's mods for everything!
Extra hilts? Yep. Better sounds? Sure. Models/skins/textures/vehicles? Levels? Yes x12! I've tried, but it's really hard to distil the copious quantities of mods into a must-have selection - Take a gander through jkhub.org
and try out anything you like! If that's not enough, there's fileplanet sites for both Outcast and Academy. They're a bit tedious to use, but still have some older things that haven't been re-uploaded to JKHub.
And remember: if a mod isn't working, you can probably fix it yourself! pk3 are just zip files, and 90% of their contents is easy-to-parse plain-text scripts. Go wild!