Here's my tip:  GO TO BANKS!! Bahahaha!!   

No, seriously.... what little success I've had there during this time of year has been on jerkbaits and crankbaits on points.  When the crankbait bite dies, switch to Texas rigged grubs and just swim them back to the boat.  Carolina rigged lizards also work. 

That pattern worked for me years ago and I haven't been able to replicate it since, but it helped Larry S. and I garner a 2nd place finish in the team tournament.

As for the sunken towns and river channels - I don't know where those are.  How do I find out?  Is there a topo map somewhere?

Chris,
I garnered a 3rd place finish a couple of years ago with a mojo-rigged 4" watermelon-colored Sammamish Tackle pencil worm.  The bite was most of the day on Saturday in about 8'-15'.  I was using a 61/2 ' MA Shimano V series rod with a Shimano 2000 Symetre reel spooled with either McCoy's or Excaliber 8' test.  When that slowed on Sunday I switched baits to a 5" Zoom lizard in pumpkin w/black flake. All those SM were caught in a creek channel that bisects a large flat about 1/3rd of the way down the lake, west of the Kosmos launch.
On other occasions I have caught limits of small fish by allowing the wind to drift me over the flats in front of Kosmos launch dragging grubs, tubes and lizards in assorted natural colors.
One of my better days came in July of 99 early in the morning in a bay near the west-end launch identified with a large concrete tower in the middle.  The water was extremely high and there was a lot of grass under water.  I caught LM after LM in the early morning heavy fog on topwaters & then jerkbaits over that submerged grass as the fog burned off.  When the sky cleared the fish went striaght to the bottom and became very difficult to catch with only an occasionl LM being pulled in on a 6" lizard Texas-regged.  This was when I 1st met Rob Rinta of St. Helens, but that is another story.
Riffe seems to give up LM's only on occasion, and only in a  few places, but that day must have been good for about a dozen in about 3 hours.
There are a few topo maps of Riffe, and I've even seen one that shows the old townsites.  If the water level is low enough you might be able to see a few scattered foundation remanents along the creek channel in the flats between Tadepaum and Kosmos.
Anything else you need to know?

Those are some great pictures. They were a real shock to me cause the only time I ever  saw the lake was in July, 1995. I have picts of me swimming and the water was gin-clear and at normal levels I guess, cause it looked way different than that. Those areas are all covered by water now right?.............Rob

P.S. Thanks, Smitty, for the detailed response... Nothing else for now!