I'm actually only just going in to my first year of University, and I have changed from Politics and Law to Political and social Sciences, because the course focused more on what I'm interested in.
As far as I'm concerned, this "modding" is very simple and basic compared to the lengths modders go to in other games, I have no where near the skill level required that some modders have to introduce new aspects into games, such as introducing new weapons into games.
My general rule is, Go looking through the files of the game, and Know, that the worst you can do is make the game not play, and have to reinstall it. From there on its just trial and error.
On a related Note; a beta of my UK mod will be up within a few mins of me putting this up, if all goes to plan. Be aware that I have to write the instructions on how to install it aswell, but it will be up today. It is a beta, and I have disabled a few features until I have them integrated, and have not included any characters (infact I've had to remove the default characters), so you'll have to make some characters.