Racer-X, glad to see you can make it!
Between Mr. Bond(age) and me we have the GPS stuff covered. No need to spend time and money on your end unless you want to because it's fun.
As for the CB, a handheld will probably do alright for this trip but you'll benefit long term from a permanent install. Many people here on the forum (self included) use the Cobra 75WXST. Info:
http://www.cobra.com/index.php?page=...duct_id=5&id=1
You really don't need a CB, though. A set of FRS/GMRS walkie talkies can be had at any electronics store. I got mine at Best Buy for $75. Cobra-12-Mile, 22-Channel FRS/GMRS 2-Way Radios (Pair)-PR4700-2WX
Most people in the group will probably use the walkie-talkies. Half the money, no install, real easy.
If you do decide to get a portable CB, I have a magnetic mount external antenna you can borrow if you like. Let me know.