If you can, plan to spend more time than you'd expect. A few hours is a minimum, by the time you make the exhibit round once, have several conversations that go on longer than anticipated, make a purchase or three (or more), and spend some time in the smoking area outside or where ever, and so on. Then make a second round of the exhibits to catch anything you missed. I'm fairly close to my venue, so I am spoiled, but if I plan to spend two hours, it's usually closer to four.
Pick up business cards where you can, especially for pipe carvers, pipe repair people, or other potential contacts. You may not come prepared to buy more than a certain allotment of pipes, but you may want the option of doubling back later. If you can be there at the end of the show, sometimes there are bargains that crop up, because people want to reduce their inventory as much as turn another buck. Also, you are in a better position to bid in a silent auction.
Even if you can spend little, you can learn a lot. When people see you two or three years in a row, they may give consideration to your interest in pipes.
For your wife, I'd do a little prospecting before the show following up her interests, whether it's antiques, consignment store clothing, fine art galleries, or whatever. A call to the local visitors' center might strike spousal gold, and she'll be putting the pipe show on her calendar for next year.
