Alliecampbell said:
Thanks for the comments zone they are all welcome.

Where do you get your ND filters as none of the shops round here have any? And what sort would you recommend?
Alliec
Allie
Depends on what camera/lens combinations you're using.
Assuming youre using DSLR then I would go for Cokin square filters as a reasonably priced system.
Their P series holder and filters are suitable for lenses with a diameter of between 48 and 82mm, if you have any lenses wider than that then youd need to look at their X-Pro or Z-Pro systems. There are other filter maunfacturers that make filters compatible with the Cokin system as well such as Hi-Tech and Singh Ray so plenty of choice.
With regards the filters themselves, then you have the choice of ND2 ND4 and ND8, the effect of the filters density gradually increasing from (usually) the centre to the top with the start of the gradation being either soft or hard, you would use a soft if there were no distinct horizon line and the vice versa for the hard step filters, you can also get full ND grads that have the effect over the whole of the filter, useful the when there is too much light and you want a slower shutter speed or a wider aperture.
The ND2 is equivalent to 1 stop, the ND4 to 2 and the ND8 to 3 stops, you could combine all three for 6 stops if you wanted just be aware than you can get instances of flare when combining filters.
As for where to buy them, I would have assumed locally places like Jessops would have stock of them, if not then online places like
Warehouse Express.