I bought Quilting Quickly II from Missouri Star and they're great - I would especially recommend these classes to beginning quilters. The videos are pretty well made and you can see what the teacher is doing. The teacher (Jenny Doan) is well-spoken and uses the time efficiently. I think the series is a good value - and if you don't catch something the first time around, just go back and watch it again - no expiration date.
I love The Quilting School's videos, too - I think that's Linda V Taylor's site? Watching Irena Bluhm quilt feathers is one of the things that gave me that "light bulb" moment - a breakthrough in trying to learn how to do free-motion quilting. And I learned a lot about needleturn applique watching Alice Wilhoit's videos - again, you can actually see up close what she's doing. Customer service for this site is outstanding, as well.