I think the one I found most helpful was Michael Angelo Batio’s “Speed Kills” which was originally released on VHS and is now available on DVD.
Troy Stetina’s books/CDs/DVDs for me. Although I also have Speed Kills which is awesome as well. On that same note I also have the whole Metal Method course by the same company that produced Speed Kills but I couldn’t make it very far into it. Doug Marks’ version of metal is too hair-band’ish for me.
Petrucci’s Rock Discipline was my go to, although I got a ton out of MAB’s Speed Kills too. As far as books go, Troy Stetina’s Speed Mechanics was my favorite.