I suppose the first thing you should do it review the dot product and the cross product. This help you will electronics (Coulomb's Law, Biot-Savart Law) if you do those in the future. I had an issue doing those without grasping vector products.
I guess a few other things you should remember is that the sum of all moments around a point is equal to zero in a static situation.
Also choosing which point to pivot around can help to solve those sorts of problems. If you have an unknown force that you do not need to work out, make that force go through your pivot point, and then the overall torque is 0.
Also don't forget to break your forces and distances into x, y and z components, this is done with a little bit of triganometry. You may find it easier to sum all the x components, you components and z components seperately.
I haven't done statics for a while, so sorry if I am no help.
Anyways, try looking at the following simulation. Not sure how good it is.
Torque - Rotation, Torque, Moment of Inertia - PhET