93 Jimmy dead... Help!

Recently inherited a Jimmy that was overhauled. It basically has a brand new engine, starter, sparks plugs, and several other parts. It's been running like an old champ, but the other day the battery died when the wheather changed. No problem got a new battery and boom it runs. However, after about 30 days the car didn't start again. We trying jumping it. During the first part of the jump it would just make a click sounds with each attempt when we tried to start, but after about 5 minutes of trying, the car no longer had electricity. No power locks, windows, nothing. I tried charging the old battery and sticking it in, nothing. I tested the current battery and it's actually good. I'm thinking a fuse is blown. I tested the big silver important looking fuses under the dash and they work. This happend once before on my GF's subaru and it was the main fusable link, however, I can't seem to find it on the Jimmy. Any idea's what the problem could be?

I would head back in the direction of the starters sylinoid. Or the connections at the starter.
My son just had a simular problem I fixed for him. we had a new starter installed almost a year ago and on our first snow storm he was plowing and the blazer quit. sometimes it would click and then just quit al together.
come to find out that when the new starter was installed, the installer did not line up the main power cables ear with the allignment slot in the sylinoid and it bent over cracking the sylinoids housing. Now this worked fine for almost a year so it was kinda frustrating.
removed the starter and there it was, pieces of the sylinoid broken off.
A inline fuse rarley blows at the starters connection so the first place I would look would be the sylinoid and its connections.
process of elimination

Check the smaller wires attached to the pos battery cable at the battery. This is where most fuseable links are. If you have a junction box on the inside of the driver's fender or on the firewall check the larger wires going in for a fuseable link. Most likely you shorted something out and blew a fuseable link while trying to jump it. Like maybe your helper hooked the cables up backwards.