[troypiggo (Troy)]

I'll give some links for the Lee stuff here.

Filter holder - I'm going the "foundation kit"
Adapter ring
Filters
Hard vs soft graduations
And as usual for me, link to a GND filter shots from POTN.

Good articles:
http://www.earthboundlight.com/photo...duated-nd.html
http://www.earthboundlight.com/photo...e-grad-nd.html

Wikipedia comes in handy too, sometimes.