I go to one in San Francisco every year and that's about 2 hours away with mild traffic. I have taken public transportation and driven all the way there. They do charge for parking, so it was actually cheaper to take mass transit.
One of the more interesting deals I've ever seen was 2 years ago. I was taking pictures of a Babe Ruth cut auto in a guys case to post on twitter. The dealer had lots of nice cards, about 3 of those laydown cabinets - Kobe auto's, Lebron's and rare baseball cut-auto stuff. A guy comes over with one of the largest stacks of money I've ever seen. He was a young guy - probably like 30. He starts counting 100 bills on the table. The dealer says "everything in my cabinets except the UDA Shoes? (which were Jordan, Durant and Kobe) Young guy says - yup! He gets to about $7,000 dollars and still has a larger wad still to go. I started walking away at that point because if I stare it might make a buyer nervous, but it was one of the largest in-person deals I've seen.
I've gotten some amazing deals usually. Last year COMC had a booth and a show special, so what I actually have the most fun doing is finding a bunch of cheaper cards and send them into COMC to re-sell. Sometimes east coast guys don't sell for as much - and I've gotten low serial numbered parallels for $0.25 each. The rest of the time I'm looking for odd-ball type stuff, like team patches or just memorabilia you don't see everywhere. If you like PSA/BGS graded stuff - every year someone has a box that says something like PSA 9 $2.00 ea & PSA 10 $5.00 ea. I also like shopping for Bengal cards because they sell a little cheaper on the west coast. Also, if a dealer has 2 or more I want, they'll bundle and you get a nice deal that way.
If you want the pick of the litter, it's best to arrive on the first day of the show. On the last day of the show, dealers might do a deal because he'd have to travel home with it, so it's a good time to scoop someone's entire booth or large boxes of base/inserts.
My brother attends the National every year and he basically does the same thing on a larger scale. He also likes to buy PSA/DNA slabbed autograph cards, index cards, ticket stubs ... ect since they tend to be a bit cheaper than a mainstream release.
I've also started getting into coins and have attended those as well. I find people are very helpful at coin shows - always answering my questions about things. Its cool. I recommend going to any card show you can make it to. I like to have an idea what I want to look for, but it's fun to just walk around.
Lastly, I've never gotten anything signed, but I sometimes just stand around the autograph pavilions and see the athletes sign and interact with fans. That's fun too.