Okay so now I've ordered a Garmin fish finder depth finder and I have four weeks to figure out how to use it. What's the best way to locate walleye in the Boundary Waters using these devices? Any suggestions will be appreciated.

Walleyes can be hard to spot with sonar depending on where you are looking and especially if they aren't suspending. If you are in a rocky bottom, they can be hard to see because they would be sitting between rocks or close to them making the sonar hard to detect them. If you are out in the basin fishing for them and its a pretty flat bottom you will see their little arches right off the bottom, or possibly suspended.

We have had success actually finding and targeting them during the middle of the day on the middle of a 30 ft lake. For walleye, I would almost use the sonar and down imaging as a way to find the structure that they are sitting on quite honestly, it is hard to find fish with sonar that aren't always suspended.

OK........like lyontyl suggests you use the depth finder to give you depth and to help comprehend what the bottom looks like. Although the pros can often target individual fish with some of the more sophisticated units I have never been able to accomplish that with any regularity.

A depth finder is the ultimate aid in precision trolling and precision trolling is the best way IMO to get to know a lake. Determine what depth you wish to "explore" and pick a lure which dives to that depth. Then paddle around while hopefully keeping your lure within a few feet of bottom. As you travel take note of the bottom. If it is completely smooth then it is unlikely to provide the basis of a food chain. If your a crayfish will you be found without a place to hide? Look for broken bottom, or even occasional rock piles. These are places where fish shop for groceries. Take note of interesting areas.......you may, or may not, actually mark fish. Return to these areas at various times. The more "going on" the better. The visible shoreline will also provide clues and help narrow the search. Is is cliff like or smooth on the bank? Likely to be similar (but not always!) down below.

Walleye will often school by size AND depth. Generally speaking smaller walleye usually school shallower and bigger girls slide deeper. Something to consider if size is important.

Also be advised that all fish seen on a locator may not be gamefish. Lots of fish out there which are not gamefish. Bear that in mind.

Check out some you tube videos. I find them helpful since they show you exactly what to look for.

Here is a start:
https://www.youtube.com/watch?v=8155r8G5Eqw

Get a fish finder that has a split screen sonar and downscreen imaging. That way you can see if it's a fish or weeds. The little fish icon is pretty meaningless because you can't tell the difference between a school of minnows, floating weeds or a walleye. Same with the sonar or graph. Also get one that accepts a memory chip of the lake you are on. The GPS will tell you exactly where the bottom structure is.

You need to understand the nature of the fish FIRST. Use the sonar to find areas that your target species seeks out for a given time of year. The unit you have is not very high powered so it is limited. In August, for walleyes, I would look for humps that top out in 10-30' or long gradually tapering points. Look for bait. If you see fish even better. Of course, wind blown shores, saddles or neck down areas and below rapids are a given. Fish will generally be active shallower during low light levels and deeper during mid day. Of course, results may very, but have fun figurin' 'em out!

Good advice here.
If I were you, I'd poke around you tube or some how-to books and find out about reading a lake map. Get a map of where you will fishing and find likely fish haunts and then use your electronics to tell you when you are at the spot. In August, if you can find a hump or two on the map--a spot that looks like a sunken island on a topo map that is maybe 8 or 10 feet deep surrounded by deeper water-- you'll find fish there. You might not see them on your sonar, but they'll probably be there. It's pretty rare for me to actually mark fish with my canoe unit; I mostly use it to locate structure or, like MT said, keep at a specific depth while trolling.
Good luck.

1) Analyze topo maps to narrow-in on a couple quality spots. Saddles, humps etc.
2) Go to said areas and paddle around with your sonar, looking for the "spots on the spot". Don't look for actual fish, just look for the spots that are most likely to hold them. Fish there for 20 minutes, trying 2 or 3 different presentations if one doesn't work. No fish = move on.

Look for structure underwater that holds fish like drop offs and humps. Also if you can find a small bay about 16 feet deep that is near deeper water adjacent to deeper water, fish that. The bait fish will be in the shallows and the fish will be there too.

Thank you very much for all your input. This information has been very helpful.