Try the books by Jim Dale. He is absolutely AMAZING! I've read the books each several times (yes, I was that crazy person in line at midnight at the bookstore and read them each straight through in one sitting), and I've listened to the audiobooks more times than I can count, and I never get tired of him. He does full character voices (I believe he's won multiple Grammys for them). I own the versions by Stephen Fry as well, and they just don't compare. You'll be a Potterhead before you know it!
I heard he is very good as well re the audio books! I did not wait on the lines like you did Margaret, but got the books at a normal time in the morning of release, but I too read the new ones each time in one day. I have re read them now at least 6 or 7 times.. getting ready to re read again
I just checked on the ones I rented and it's Jim Dale who is reading...I love love his voice, but I just tune it all out