hey there,
i had the same problem where i wanted to recover my contacts from my iphone backup file without using the 'restore from backup' feature in iTunes. After a bit of a struggle i managed to recover my contacts from my iphone backup. i did the following:
1) used the free 'iphone backup extractor' available at supercrazyawesome.com/ to extract the my contacts file from the backup file. when opening the app i chose 'iOS files' and clicked 'extract'. the contents of my backup were extracted and i found the address book file under /Library/AddressBook/AddressBook.sqlitedb
2) to open the sqlitedb file I tried the SQLite Browser here http://sourceforge.net/projects/sqlitebrowser/ and used this webpage to try and extract the address book file into a csv using the directions on this page: http://forums.macrumors.com/archive/index.php/t-1350341.html
However, this didnt work and i got the error 'file is encrypted or is not a database'. I don't recall encrypting the backup files so i did some research and found out that it may in fact be due to me using the wrong version of the SQL database.
3) I then downloaded Firefox and installed the AddOn called 'sqlite manager': https://addons.mozilla.org/en-US/firefox/addon/sqlite-manager/.
4) i opened the add on and navigated to the AddressBook.sqlitedb file mentioned above, and used the following query:
select ABPerson.prefix, ABPerson.first,ABPerson.last, ABMultiValue.value from ABPerson,ABMultiValue where ABMultiValue.record_id=ABPerson.ROWID
5) i then exported the contacts to a csv file, opened the Address Book app on my laptop, clicked 'import from csv', and then went into itunes and selected 'sync contacts'.
6) presto! my contacts were back on my iphone.