I haven't had much luck with tapes/DVDs.
You can look at my previous posts for YogaToday. They have a new program everyday. Be careful of the file size if you decide to save any.
I also posted about yoga free on cable with on-demand. None of them are full length - but they are by people like Rodney Yee and might give you an idea if you like the style or not.
With a couple books I've kind of pieced together a session I do on days I don't take a class. But I still think classes are best.
If you find something you like - post back.
Also have you looked at gaiam's sight? They do most of the yoga dvd's I've seen.
There is actually one that comes to mind. But I haven't seen it.
Elise Browning Miller has an intermediate dvd.
She teaches Iyengar style - which is not flow or ashtanga if that is what you are looking for.
I bought her yoga for scoliosis materials for my Aunt and was really impressed with them.