How do I reduce the noise my pick makes from hitting the strings (not through amp)? I have an Ibanez GRG170DX and am using picks from a local store.
Depends on the thickness of the pick, thin picks tend to make a bit more noise than thicker ones.
So I should be looking to get a thick strong pick? At the moment I am using a quite think pick so that might be the problem.
Over time, you seem to develop an ability to minimize the noise, and trying a thicker pick is a great recommendation.

"He who controls the past, controls the future. He who controls the present, controls the past." - Orwell
How you hold the pick and the angle of attack on the strings makes a huge difference as well. I can use a thin pick and not get much pick noise by changing how I pluck each string. Instead of hitting the string flat on with the side of the pick, angle it so that the edge hits the string first. This is also helpful for speed. Big fat picks are good too, but take a bit to get used to if you've been using thins.
^ probably the best responce yet. Eventually you will be able to minimise it naturally with your angle of attack on the strings. Thinner picks do also tend to make more noise because it scrapes across it more usually. Thicker picks tend to be quieter but do require more practice to get used to it. When I started I could barely touch a thick pick and strum but its a ton easier now. Try also holding the pick further towards the tip, you should hold it with only a small portion sticking out (Meaning no less than half really).