Well, I have only really started, and I dont have enough cash (currentlly, 90k) for the schools, so I am taking starter courses at a junior college. The class is more about the whole process not specific things like levels. Try to download a trial version of 3d studio max. That is what most game designers use for the creation of their gamers. Also download the tutorials that I belive should still be on the site. Some things I already know and some I don't. Mostly, it has to deal with how to come up with proposals and writing stories and ideas, and hte like. This class doesn't really go into how to physically make it, not in any indepth manner. The instructor does give side lessons and what not, just to show you what it is that the various departments(writers, animaters, story boards, modelers, coders, etc.) have to go through, but you don't have to do that your self. This is basically about coming up with an idea and saying you have the people to do it, so here is how you do it.

I've signed up for a modelling (no not that type of modelling) and animation course at college next year, though not specifically game related, it's a start, games need animations!

I have Google Sketchup as well as Maya, which has laid a pretty good foundation, I know all the basics etc etc, can't wait 'til I start!

I would advise against using Sketchup as it isn't a formal 3d modelling program.