Like a lot of folks here who are moving from apple to droid, I've been trying to learn about the android system while I wait for my phone to arrive. I found these articles on PC World that were pretty helpful (to me, at least).
Master Google Android: 40 Tips and Tricks - PCWorld Business Center
Android 101: A Guide to Using Your Android Phone - PCWorld
Verizon's Droid X: 12 Apps to Get You Started - PCWorld
If anyone else has some useful links that explain basic aspects of using android and the droidx, I and others would find that very helpful.