Silk screening sounds awesome! It's a shame the equipment is so expensive. How do you plan on improving? Do you have all the equipment?
You can DIY silkscreen for just a few bucks. Youtube also has a ton of videos along these lines. Basically, if you just want to make tee shirts for you and your friends, it's totally do-able. Also, here is a guide that gives some pointers and common mistakes for beginners to avoid. I'd search youtube for 'DIY silkscreen' though. It's like the wikipedia of getting shit done.
It's something that I've been working towards for about four years now. I have all of the equipment needed, but I've been putting it off for some reason. I also took a beginner's class a long time ago, so I plan on taking a few more classes to get the ball rolling again.