I found the show in Tacoma to be a little underwhelming, but knives are always nice to see.
I believe the show in Puyallup Ron mentioned is the Washington Arms Collectors show. They have a couple every month I think, some are in Puyallup and some are in Monroe. The ones in Puyallup are at the fairgrounds. It's five bucks to get in unless you have a membership, which is twenty (but I wouldn't sign up this late in the year, since it's only good through 2000)..
At the one this weekend I saw some handmade knives f/s by maker, some boxes of old bayonets, some private collections, some junk-drawer knives, a couple of tables selling Spyderco, Benchmade, Cold Steel, Gerber etc.. I usually also see a couple of guys who have some CRK stuff.
Note that knives are not the main focus of the show -- there were also blowguns, hunting stuff, beef jerky, survivalist literature, guns, ammunition, and, for some reason, beanie babies.
There's not usually much of a selection, I mean, I'd love to go to a real blade show sometime, but it's a fun day out anyway.