I was never much into exercise before, but I've discovered I really like yoga. I knew very little about yoga until I started taking yoga classes in January 2000. It combines strength, stretching, and balance. It can be a surprisingly strenuous workout, yet it's relaxing and peaceful as well.
After talking to several friends who already did yoga, I decided a beginning Hatha yoga class would be good for a newbie like myself. I found a nice web page listing Austin instructors and went to several different instructors and locations to get a feel for what was available. I also wanted a class that was philosophically compatible (which for me means not much emphasis on religious or new age stuff). A seriously "hard edged" person might not enjoy yoga (e.g. every class I've attended closed with a peaceful guided meditation, which can veer toward the new age end of the spectrum, but they work for me). I found there was plenty of variety in the instructors as well as in the types of locations, so I was glad to have tried various teachers & places.
Most instructors let you drop in on a class for $10 or less. Then you can sign up for a block of classes at a discount rate if you like, typically working out to a couple bucks less per class. You don't need any special equipment except maybe sweat pants. You normally do yoga barefoot. Some folks buy a "sticky mat" so their feet don't slide, but I've not found that necessary.
Here are some useful yoga FAQs:
Frequently Asked Questions of alt.yoga
Here's an unintentionally humorous longwinded religious right anti-yoga diatribe. I hadn't realized before that some fundamentalist Christians regard yoga as an anti-Christian thing. Sheesh.
Here are some comic strips I've done involving yoga.