You can manage your library so that all your music is in your library but with a Match/ Upload limit of 25K plus Purchased Music.
Create a second blank iTunes library http://support.apple.com/kb/HT1589
Sign into iTunes Store and match. You will see all tracks in the cloud. You can delete excess tracks from the cloud. This will not remove the music from your computer and when you go back into your original library, the songs will still be there. The iCloud status for them will now be "removed" and will be ignored in match updates
My apologies Michael & Jim. I didn't read it fully.
Now, after reading fully and foloowing your instructions, I am still getting the same error:
"Your library contains too many songs.
To participate in iTunes Match, your library must contain no more than 25,000 songs that were not purchased from the iTunes Store."
I spent the weekend deleting songs in the second library (after signing onto Match). I got it down to 23,000 songs. I went back into my origianl library and got that same error.
This is a major pain...and a lot of wasted time, ripping, deleting songs, then deleting songs from Match. I wish Apple would just make an easier way. I know that someone likle me is not the majority, most people have much less than 25K songs, but we are customers too.
Thank you guys for trying.