I think the class would be worth the money, especially at that price. I've never taken this class, though. I have flipped through the Wilton cake decorating class books, which I covet because I think they are cute.
Anyway, I am a cake decorator in a bakery. I had no idea how to decorate cakes (or ice cakes) when I started training. I learned from someone who is artistic and very good at cake decorating - so this was a bonus for me
The Wilton books do a good job of describing the angle at which you need to point your pastry bag and whatnot, but these things are hard to grasp in general if you've never seen someone actually holding the bag and forming whatever is they are doing (roses, shell borders, etc). There are lots of books (I tend to find all the 80s ones....) at your local public library with information on cake decorating techniques, themes for birthdays and weddings, etc. Its worth a look.
Practice! I wish I had all the tools at home to practice, but I had to rush through it at work, which I guess was OK in the end--just stressful. (I still don't have tools at home to do my own cakes, come to think of it. ) With time, you'll probably realize the things to take your time on (color matching, icing the cake level, other things you feel are important) and the things to just get done (just slap that icing/filling in between the cake layers, dont fuss because no one else is going to see it!)
I'm rambling a bit now. I hope you got something out of this post
1. watch other people who know what they are doing
2. practice what youve learned
3. dont give up when it doesnt look how you imagined
4. feed your brain with books from the library!
p.s. here is a link to 3 of the cakes i have on my flickr. this is by no means a complete portfolio haha. ive done... probably close to 400 cakes just this year so far.http://www.flickr.com/photos/wendywears/tags/cake/
GOOD LUCK! feel free to email me with any questions