Nicks in the top sheet are nothing to worry about. Unless they are down to the core. Next time your in the lift line take a look at all the nicks in the top sheet on the skis around you.
As for turning go to www.tognar.com
Tognar Toolworks. order there catalog. Another good place to go is www.artechski.com
for Artech Racing out of NH.
There has been a lot of talk here lately about tuning, I use the MoonFlex diamond stones, not cheap but boy are they great. I use a 200 grit and 600 grit. Mostly use just the 200 grit. A small panzar file, and SVST edge guide. A buudy just bought the Swix 1.0 degree base tool, that seems to work will but I don't touch the base edge much.
Becareful with the panzar file it will remove a lot of edge quickly.