I made the mistake of going near a camera shop on Saturday and came out with a Cokin P-system polariser and two grad ND filters.
I understand there may be issues with the GND's but I think I'll make sure I will actually make real use of the setup before looking to more expensive filters.
Thanks for the kick in the butt about using the tripod. I think I'll have to invest in a more user-friendly ballhead, but I'll strive to use it more.
From quick playing about yesterday I've already learned that the spot meter doesn't work in quite the way I thought it did
, that placing the GND's might take some getting used to, and that all the shots with the polariser are massively underexposed and I don't really know why.