Well, a couple of things come to mind:
For the reservoir, could mount it at the back of the cooling pad (e.g., the higher end) so that you can see it, use an acrylic one, something like
http://goo.gl/uUUsp
Aren't all good laptops just portable desktops?
With the quick disconnects, you'd need to have some give in the tubing, so that you could lift up the laptop a few inches so you could reach the disconnects. I don't think that would really be a huge issue unless you're using huge tubing in a small cooling pad lol.
EDIT: Looking back at that res, it would work really well lol, on its side its only 1.5" tall, which isnt unreasonable at all for a cooling pad, and it has intakes for filling on both top and bottom so you could use that as a fill/drain port, out the side of the cooling pad