Welcome aboard!
Start here:
http://www.subsim.com/radioroom/showthread.php?t=192374 and all shall be revealed.
There is no easy way around it, you'll need to read a lot! When I first started out I felt the same way. Sober has done a great job selecting the mods and has links for everything.
Grab a bag snacks, a cold pop and read. It will all pay off.
PS: Not sure if you can use the new exe patches on the Steam version or not. Someone will jump in. If you can't order the dvd. It's a blast.