[Hondasucks]

click but no crank usually means corrosion on the contact disk or contacts in the starter. Pretty simple to fix, take the starter off and remove the plate from the back of the solenoid (Part of the starter where the big fat wire from the battery is connected), remove the plunger and clean the copper disk with some fine emery cloth, and do the same with the two copper contacts on either side of the housing. If either one of these are badly burnt or pitted, they will need to be replaced, I'm not sure if they are available from Subaru, Toyota sells them individually. (The Toyota ones can be used in a Subaru starter, you just have to make sure you get the right ones as there are a few variations).

I've also seen this problem be caused by the starter disable relay in the security system, had just enough corrosion on the contacts to allow just enough voltage to the solenoid so that it would click, but it wouldn't engage the contacts so the starter wouldn't turn.

A bad B+ (Battery) connection at the starter would also cause this problem.