There's lots of threads about pre-shot routines; which aren't restricted to the game of 9-ball. It's a pre-*shot* routine, so it works for any shot in any game.
Typically, you want your preshot routine to be exactly the same each and every time. From where you start looking at the shot until after the balls stop moving after the shot. For example, my routine is something like this:
1) Locate the target area for the cue ball for next shot (if running out, otherwise, safety location).
2) Determine best pocket for object ball to put CB in target area.
3) Identify contact point for CB-OB (line of aim, or however you do it).
4) Stand behind CB along that line of aim and calculate english requirements, etc.
5) Step into and get down on the shot, get comfortable bridge/stance/grip.
6) Practice stokes, turn off conscious brain.
7) Execute the shot, stay in finish position until *at least* object ball drops (if you can without interfering with CB path, of course).
8) Stand up, breathe, start over.
As for drills, look up ForceFollow on youtube, or even better, go through his extensive video library on his website:
http://web.me.com/forcefollow/Site/Video_Library.html - Pay particular attention to the Drills section.
Another good youtuber for drills is FastMikie.
Lastly, look up the IPAT drill books and videos; they are mostly related to 9-ball in the later sections.
Enjoy!