Here's a link to the battery back-up that I used, for anyone that's interested:
http://www.handhelditems.com/mybat-3200mah-backup-battery-iphone-ipod-black-p-4790.html
Sally, I also agree that the Itouch is great because of all the apps you can run on it. I'm a fan of Tripit.com & I created my itinerary on Tripit & then used their app to access my itinerary on my Itouch. I downloaded it onto both of our Itouch's so that my husband and I always had pertinent information at our fingertips (phone numbers for hotels, addresses, train information, tour confirmation information, etc.)
I also downloaded all of my contacts from Outlook into my Itouch & had everyone's addresses handy for sending postcards. I downloaded several games onto my Itouch prior to our trip and often played games while waiting in lines, on the plane, etc. I also forwarded all of my trip-planning confirmation e-mails to myself via my Itouch & that way, I didn't have to carry a stack of printed e-mails with me. We also scanned our passports & e-mailed them to ourselves so we could access them on our Itouch if we lost ours. There are just countless ways that the Itouch made our trip easier! I don't mean to sound like an advertisement for the Itouch but it really did come in handy. Have a wonderful trip!!