We've driven people and kegs/gear to Florida, Ohio and Minnesota, and shipped kegs and gear to Denver and Oakland, from Maryland. Next year's trip to Philadelphia will be so easy in comparison, I don't think we'll know what to do.
If you are doing Club Night or hospitality room shifts, once you sign up you will receive instructions on labeling your beers. Cold storage will be provided, so all you need to do is deliver your properly labeled beers and then go have fun. Your beers will be delivered by the cellar folks to the proper venue for whatever event(s) you sign up for. You will be responsible for your own hardware, including CO2. So bring tools...and if you don't think you'll need something, definitely bring it. You will be provided with ice and maybe tubs for your kegs or bottles. We have a 4-line jockey box and half-fill it with ice, and serve other kegs we bring out of tubs or buckets with a little ice. The beers are brought out cold, but they'll also sit for a good hour or two while setup is happening.
Our club has done Club Night every year for the past 7 or 8 NHCs with the exception of this year in Seattle (which we attended individually rather than as a club). Our booth tends to be simple, with either a jockey box or our portable bar. Other clubs do very ornate, themed booths, but I guess we're just not that clever. We also bring a food item or two representing our local cuisine. The more complicated your booth, the longer it takes to set up and break down. Our banner mounts to a PVC frame about six feel up in the air above the fray so that it is visible across the room. Make sure you also make a fairly large menu of your beers that is easily read by people walking up or waiting in line. We use a white board on an easel. That's about it. By the time the evening is done and we've been drinking a room full of beers, the last thing we want to do is kill ourselves dismantling a complicated booth and hauling it out to our cars or up to our rooms.
How much beer you bring is up to you, but if you do Club Night you'll want to have at least 6 or 8 different beers. We have killed whole kegs, and we've brought half-full kegs back home with us, so it's hard to know. The more unusual (and good) your beers, the more traffic you'll see. If you have something really special, word will get around the room. OTOH, a keg of IPA will probably be one of several dozen IPAs in the room, so you will probably not go through a whole keg of it.
Serving at a Club Night table is a ton of fun. There's nothing more rewarding than having someone from across the country come up to you after a couple of hours, and tell you that one of your beers was the best one he/she had all night. That said, you will only have a 6 or 8-foot table to stand behind, and if you have more than a few members in attendance it is worthwhile to plan on taking turns behind your booth serving. More than 4 people and you'll get in each other's way. Plus you'll miss out on all the other beers, food, and fun displays.
Don't forget to eat. And don't forget to drink lots 'o water. It's very easy to forget both.