How do I see which computers are authorized for my Apple ID? My list of devices has one computer (plus my iPhone and iPad), but my Apple ID summary says there are two.

There is no such list. You can do this:

Deauthorization

You can de-authorize individual computers, but only by using those computers. The only other option is to "de-authorize all" from your iTunes account.

1. Open iTunes on a computer

2. From the Store menu, select "View my Account..."

3. Sign in with your Apple ID and password.

4. Under "Computer Authorizations" select "De-authorize All".

5. Authorize each computer you still have, as you may require.

You may only do this once per year.

After you "de-authorize all" your authorized computers, re-authorize each one as required.

If you have de-authorized all computers and need to do it again, but your year has not elapsed, then contact: Apple - Support - iTunes - Contact Us.

For more information on authorization and de-authorization: iTunes Store- Authorize or deauthorize your Mac or PC.

Go to the Account Information screen in iTunes - Click your name at the top of the iTunes window, and then Account Info.

On your Account Information screen, there is a link for Manage Devices under iTunes in the Cloud. This shows a list of computer and devices currently associated with your Apple ID.