If you don't find the mod your looking for (easily) in the downloads go to the mods workshop forum and do a search for the mod in just that forum; it'll pop out some false positives but the thread with the download will usually be one of the first 5 or 10.
This thread:
http://www.subsim.com/radioroom/showthread.php?t=170090 is a good one to go through. It's got lots of good screenshots of various mods, guis, and other goodies. There are a lot of great mods out there (most of which you can see in that thread) but take it slowly. Adding on a dozen (new) mods all at once can cause problems which are hard to trace when you activate so many changes at once. A good number of mods require other mods as depencies and have to be installed in a specific order to get them to work correctly. Happy hunting
