When I started using Encore (at that time I was using Premiere Pro) I found the free and easily available tutorials from Andrew Devis REALLY helpful. As alluded to in my workflow earlier, I create a Master out of my FCPX project anyway for archive purposes and it is that (or the compressed version of that out of Motion) which I use in the principal timeline for my Encore projects.
I don’t think there’d be a unique tutorial covering both FCPX and Encore as at least in my workflow it’s just a question of Encore picking up where FCPX (and Motion for when I feel I need to use it) leave off.
For a few years I used the Encore templates but it’s so easy to create your own moving backgrounds with sound within FCPX and you have SO much more control over everything. As far as button usage is concerned, within Encore I practically always use the one called “Atomic Video Button” found under the “Technology” section. It’s good and bright and I always click on “Animate Buttons” on the Motion tab over on the Properties pane.
If you do decide to use Encore then there’s a forum for it here on CCow with lots of helpful people.
FCPX and PPro 6. iMac 24 + MBP 17″. Near Geneva, Switzerland