Most of the time, I only import the songs I like from an album and not the whole CD.
To keep the number of "albums" I have down, I type in "Singles" as the album title in the tracks that aren't in a whole album in my iTunes library. That way, I can see which full albums I have and the number of albums I have is correct.
"This script will collect the "one-hit wonders" in your iTunes or iPod library—every track whose artist is represented by just a single track—and copy them to their own playlist on the respective Source."
If you're on a mac, you might want to check Doug Adams' new applescript out:
http://www.malcolmadams.com/itunes/scripts/ss.php?sp=gatheruptheonehits
"This script will collect the "one-hit wonders" in your iTunes or iPod library—every track whose artist is represented by just a single track—and copy them to their own playlist on the respective Source."