Plugins Are Great, But They Require A Lot of Fine Tuning

Sometimes plugins don't work or they break, this can be very annoying and time consuming to fix but they are what make some servers better than others.

plugins.bukkit.org/

Other good websites:

http://www.no-ip.com/
http://mcserverlist.net/
http://forums.bukkit.org/
http://www.youtube.com/user/KingzofME

My Personal Server:

thebossserver.hopto.org
(type this into the multiplayer ip window in minecraft)