The circle windows on the right side, just behind the cockpit area. Some have 3, mostly 2.
This one has one window and the other has become like a small door, the one at the wing root now becomes a window, but no long cables/wires at the top:
http://www.airliners.net/photo/USA---Air/Lockheed-Martin-C-130H/2489688/&sid=48c8a05a90db3f7206a6ab80991f2ee7
And...
This one has three windows, with long cables/wires at the top:
http://www.airliners.net/photo/USA---Air/Lockheed-C-130H-Hercules/2456473/&sid=48c8a05a90db3f7206a6ab80991f2ee7