Q: How do you know what devices are connected to your apple id

On computer iTunes > Store > View Account > sign in with your Apple ID > in section iTunes in the Cloud, click Manage Devices.

If you mean the list of computers authorized to play DRM-protected iTunes Store content, it’s not available from your end.

If you mean the list of computers and iOS devices associated with your Apple ID for downloading content from the iTunes Store, click here.

(120514)

Just change your Apple ID password then.

If it’s an authorized computer(see the first paragraph above), you can’t individually.

If it’s an associated computer or device, click on the link I posted and then follow the removal instructions.

If it’s an iPod model other than an iPod touch, it doesn’t take up a slot and can’t be individually removed/deauthorized.

(120516)