Here is a couple of photo expamles with the graduated filters you can get at www.formatt.co.uk
Get yourself a Cokin P filter holder off ebay and a set of 85mm ND Grads from the above site.
These filters can be very helpfull for landscape photos, especially if you are getting washed out skies (Grey) a lot. Basically these just put some shaded glass over the sky portion of the photo.
Here is a pic taken with a 0.3 ND Grad. You can see the clouds are nicely exposed.
Here is the same phot taken with a 0.9 ND Grad... You an see there is a lot more light fall off at the top of the frame.
Something to mull over.