to locate your itunes back up:
On a Mac: ~/Library/Application Support/MobileSync/Backup/
On Windows XP: \Documents and Settings\(username)\Application Data\Apple Computer\MobileSync\Backup\
On Windows Vista and Windows 7: \Users\(username)\AppData\Roaming\Apple Computer\MobileSync\Backup\
then use any of database programmes to read the .db files. I personally used SQlite Database Browser 2.0 (please note I used this on my mac and can't remember if there is a windows version-but there are loads of other Windows programmes) and from there you can import into a .csv file and read in excel (more detailed instructions can often be found on the sites of such programmes, sorry, I am typing this from the top of my head, hence no further detailed instructions)