Q: how do i set up an additional ID for a work phone

You can create a new iTunes account via http://appleid.apple.com or via your computer's iTunes : http://support.apple.com/kb/HT2731

If you don't want to give credit card details when creating the account then follow the instructions on this page : http://support.apple.com/kb/HT2534

All content that you download from the store will be tied to the account that downloads it, and if you use iTunes Match, automatic downloads or redownload an account's past purchases then you might tie the device or computer to that account for 90 days : http://support.apple.com/kb/HT4627