Merge Apple Accounts
I want to deauthorize one apple account and still have access to the music. In essence: I want merge two accounts. Is this possible and if so, how?
You can have more than one account authorised on your computer's iTunes via the Store > Authorise This Computer menu option, but it's not currently possible to merge accounts - content will remain tied to the account that originally downloaded it.
Also only one account can be signed in at a time for purchasing and/or re-downloading content - and if you re-download content from an account then you risk tying the computer to that account for 90 days : http://support.apple.com/kb/HT4627