Want to learn the new iMovie
I'm generally a fan of Lynda.com. If you are a student (especially in a college environment), you may have free access to Lynda at your library. It looks like there are a series of tutorials for iMovie on their site:

http://www.lynda.com/iMovie-training-tutorials/229-0.html

Alternatively, if you search Youtube for iMovie training, you'll likely some good stuff as well (even reposted Lynda.com videos). I suspect that after about an hour of video tutorials you'd have a good sense of the key features of iMovie.