1. Always wear comfortable shoes, bring a back-pack with supplies and snacks, and don't dress too warmly... it's normally room temperature whether it's November or May.
2. Always look around for better deals. Never take the first dealer as the best price. I wandered the Expo on Saturday and saw 2008 SPx Baseball at three different tables. One for $240, one for $160, and one for $100. Guess which one I bought. And imagine how sick I would have felt if I purchased the $240 box and saw the $100 box later. I'm doubting that dealers allow for returns on unopened boxes.
3. Prices change through-out the day and the weekend. If something is too high on Friday, it might be lower on Sunday. And vice versa on the hot products. Some dealers want to move product on Sunday so it never hurts to make an offer, especially if you're buying more than one thing.
4. The Expo Redemption Programs are fun and you get a nice bonus... but the line-ups can be tedious unless you have a friend with you. However, it's a good way to meet fellow collectors if you are social. My Upper Deck redemptions were less than special but a friend of mine lucked into a Wayne Gretzky auto #/5. He was offered $600 on the spot. (He turned it down)
5. The autograph guests during the 3 days are numerous and span many sports. It can be cheap or expensive depending on the player. If you're from a place where you rarely see sports stars, it is a great opportunity. I've had the pleasure of meeting Gordie Howe, Gilbert Perreault, Claude Lemieux, Kelly Gruber, Gillian Apps, and Phil Goyette.
6. The more money you spend on food, the less money you can spend on cards! :)