Practice and experimenting will help a lot. There is (was?) a book out called Precision Trolling that would give you trolling depth of just about all the major baits.
Another option to control the amount of line out, is to mark your line every 10 feet. Diawa has a line counter that can be had for about $65 new if you're going to get into it a bit more.
I like the shad raps and the deep taildancer. For me, for walleye, in the water I fish the most I like: perch, silver/black minnow, and gold/black minnow.
How fast/slow to run the outboard depends on the size of the boat/motor and conditions. But yes, usually just above stall, or a little faster will work. Don't forget to check how the lure is running at the side of the boat at the speed that feels right.
The baits like the original rapala and the husky jerks work really well but, need some weight to get down below 5-7 feet. This can be done with either a split shot or two or a bottom bouncer or 3 way rig. I find that the split shot option is nice and subtle but more prone to snagging then the other options.
A web search should turn up some other options as well.
http://www.thenextbite.com/Precision_Trolling