the latest craze is
single columns ui . i've been messing with it for a few days as it allows you to display album art in the playlist.
as arty says, you need to spend a bit of time over at hydrogenaudio.org (follow his link). not so sure about the great community though. it can be a bit intimidating if you ask noob questions....
best thing to do is a spend awhile lurking.
for this particular plugin, you have to have album art already. it will not fetch it for you. i use this to get my album art-
http://team.thenexusnet.com/nexus/AAA/
and for tagging files from the freedb database, the latest foobar version has a component builtin but unfortunately it's pretty crap compared to the 0.83 version...