i've bought a couple of lecture pads to be used only for lectures (u don't necessarily need one pad for each subject - just rip the notes out and file in a folder for that subject as u complete them) Make sure u put the subject, title & date on all ur notes though, so it's easier to stay organised.
then i have a five-subject notebook for tutes 'n stuff - one section for each subject - (i'm gonna tear those out & file with the lecture notes for that subject, in chronological order)
mehh... doesn't really matter either way - i'd personally prefer to keep lecture notes and tute work separate to start with (and later put them together), but whatever works for u