Well, my experience of BEC (BookExpo Canada) is somewhat unique, but I'd definitely urge you to go.
It's been a long time since my first one, but I remember feeling incredibly overwhelmed, adrift, and giddy with excitement. I was there as a bookseller; you'll have someone from your publisher to show you the ropes, to make sure you get to the Children's gala (one of two big parties the night before the trade show opens), that sort of thing. Or you could lean on a friendly west coast bookseller (though don't lean too heavily: I'll probably have been drinking, no matter what time of day).
It's a great opportunity to network, to meet people who can make a real difference in your career, and to get a sense of the industry as a whole. I go every year, and I highly recommend it. It is pricey, but you get out of it what you put into it, and some good connections are priceless...
