Would this fit my camera?

Http://www.futureshop.ca/en-CA/product/rocketfish-rocketfish-52mm-circular-camera-polarizer-rf-cp52-rf-cp52/10149861.aspx?path=efbf02a72653e62143a70da5d0fd2ef9en02

This is my Nikkor lens size but will it fit my Nikkor? Its the 18-55mm that came with my Nikon D3100. Thanks!

Added (1). Fhotoace: What do you mean by thread size or whatever?

I can tell you did not find the filter thread size on your lens. It is 52 mm

"Whatever" is the most important thing to know when buying filters. Filters screw on to the front of the lens. For that to happen, you have to know the filter thread size of the lens you plan to attach the filter to. There are many lenses and not all have the same sizes. You pick the right size of filter for your lens. Luckily, the filter in the link you provided and your lens have the same size.

18-55mm is the focal length of your lens, not the lens size. Focal length is more about angle of view.