trolling is as easy a thing to learn as any, except that everyone does it differently and that they're all right if they are catching fish. so where do you start? you can troll anything at any depth, but you'll probably realize quickley, and have probably read a hundred times, as the water warms and the sun gets blazing on the surface of the water the fish go deeper. i guess i'm saying that if you are trolling durring the middle of the day you have to fish deeper then at sun up and sun down. if you don't have a depth/ fish finder it's more work but worth figuring out where the fish are hanging. sawyer gets nice and deep so there's room to play with a downrigger, but if you fish early enough you won't need it. anyway my best guesstimt is early you can catch fish in the top 10 to 12 feet of water by say 10:00 go from 10 to 20ft and by 1:00 fish from 15 to 35. who knows maybe at 3 in the afternoon with the sun roasting and the water warm you'll catch fish on the surface, probably not, but there's no one "right" way to do it so just keep playing until you get strikes.
as far as what to drag, rapalas from inchers up to size 9, if there are perch and rainbows in the lake use those colors, the gold works great as well. small thin spoons up to 4 inch, frog colors, silver/ blue combo, gold/ flor. orange combo. pop gear/ wedding ring/ worm seems to be a stand by for all northwesterner's. my luck has always been with smaller bladed pop gear(marketed as kokanee size). ofcourse you can tip spoons with maggots or any other bait you want so long as it doesn't effect the motion of the lure. chances are you've got things in your tackle box already that will work great so you don't have to go and spend a ton of money to catch fish, though that'a always fun.
somebody who helped me out recently recomended a book explaining trolling called the art of trolling, it looked great. also at outdoor emporium in seattle there's a great book on downriggers right near the downrigger stuff.
good luck let us know if you're catching anything!