I have a work around! I too miss the old WMP toolbar from previous versions and have a solution. It involves reverting back to WMP11, which IMO is WAY better than WMP12 for more reasons than just the toolbar. I am starting a new thread with the heading: Windows Media Player 11 in Windows 7 - WMP Toobar. I'll post it within a half hour - I just need to write it up.
I don't see how this is really a solution to the problem. The following works for WMP12 so you don't have to downgrade:
obtain a copy of C:\Program Files\Windows Media Player\wmpband.dll from a computer with WMP11 on it (for the same type of os, i.e. 32/64 bit)
place this file in the C:\Program Files\Windows Media Player\ directory on the computer with WMP12
stop the Windows Media Player Network Sharing service
run a command prompt AS ADMINISTRATOR
execute the following command: regsvr32 "c:\Program Files\Windows Media Player\wmpband.dll"
restart the Windows Media Player Network Sharing service
run Windows Media Player 12 and minimize it
right click on the toolbar -> toolbars and select Windows Media Player
That's it, if you have any problems try performing the preceding steps after a clean reboot and before running windows media player.