I think many of the basic drills are fairly standard and can be found in different books.
Here's what I do: I almost always warm up with drills from Zaner's 'Lessons in Ornamental Penmanship' and/or Bloser's separate book of the same title, plus other drills I think are useful. I do ovals (direct and indirect) on the main slant, then horizontal ovals (both directions again), then a push-pull drill on the main slant, then "infinity" drills (both directions), then a bunch of other drills. I've recently begun following Bloser's advice (at least, I think it was his) to do them with my forearm off the table. That's helped my control a lot.
I think the oval drills, the push-pull drill, and the "infinity" drills have helped me the most. I'm still a beginner, though, so take all of this with a huge grain of salt.