Quote Originally Posted by RebelT2 View Post
.... my lens takes 58mm screw in filters does any one know if they will fit or need to buy adaptor rings?
You ALWAYS need adapter rings!
the Cokin filters have a square shaped holder where the filters slot into(on one side) and on the other side of the holder is a circular recess where the adapter ring slides, and clips into as well. That circular shape is set, and can fit up to an 82mm lens thread.
The reason that the rear recess of the filter holder is circular is that you can rotate the filter holder to suit your scene.

I think(I'm not sure) that this landscape kit may require you to purchase the adapter ring separately, and all you do is specify the size of the threads(in your case 58mm!).
Then when you get yourself another lens with a larger diameter front element, all you need to do is purchase another adapter ring(approx $10-20) or so.