Here's the tree: Adobe's Design Center Video Workshop.
The workshop includes tutorials on 47 different topics involving many of the tasks that can be accomplished by Adobe applications. In addition to being categorized by topic, videos can also be found by selecting the various Adobe applications on the top right-hand box of the workshop.
And the best part about these videos, other than the fact that they are free, is that they are developed by Adobe professionals. No where will you find better answers on Adobe's products.
Please note that you will need to have Flash player for this work.