My very favorite item at the expo was The Humunga Tongue, by Moody Pet. It's basically a rubber ball with a long tongue-shaped appendage. Your dog bites onto the ball and tada... it creates the silly illusion of a gigantic tongue! Every dog in America should have this toy!
I also found a great "busy brain" toy by Premier called the Busy Buddy Twist 'N Treat. It looks sort of like a fat purple flying saucer, and it unscrews in the middle so you can fill it with puppy snacks. I'd seen their bone toy before, but never this squashy-ball-shaped version. As with all fantastic puppy puzzle toys, the goal is for your dog to figure out how to get to the treats. It's adjustable, so you can make the treats easy to get to for beginners, or more difficult for those dogs who are well-seasoned pros.
One of the vendors had Tuffie's Giant Dino Toys, which truly live up to their name: they are HUGE toys (ideal for large breeds) and they are very very tough for a "furry toy" (PVC in the center, covered by two layers of supersturdy nylon, topped with one layer of fleece for stuffed-animalesque softness.) The Dinos available include: Pterodactyl, Stegosaurus, Triceratops, Tyrannosaurus, and "Tuffzilla" (who stands almost 3 feet high!) These guys are so ferociously cute that if you have kids, I guarantee they will want to Dinonap them!