Probably the best tool for finding something like this, aside from the wiring manual, is a circuit breaker that clips into the fuse box in place of the blown fuse, this allows the circuit to be safely energized long enough to track down the short. If you don't have one of these it can be really tough. You can try poking around with an ohmeter but you may not find it this way. If the problem is an electronic module that isn't really shorted but draws too much current when powered an ohmeter won't find it.
Post if you find anything or can use more help.