How long should I wait before taking my fence contractor to court?

First of all, you don't say where you're located. If you're here in NE Ohio, I wouldn't expect the work to be done yet due to snow and frozen ground. Concrete needs a minimum temp of the ground to set or he might as well not put it in. I'd try and have another conversation and ask him what's up. Even if he can't afford to buy your new materials that you've already paid for with your partial payment, he should be able to remove the piles of old fencing (unless he has to pay disposal fees). You may find out that he is a good guy and has just gotten caught up in his own fiscal problems. I wouldn't take him to court yet, because that costs even more money.  more