Dog in boots is hilarious--but don't laugh at him/her, if you want the dog to learn to tolerate the boots!

Jim, re warm dog jacket that covers most of the belly, here's a site that makes thick fleece ones: Apache River Dog Coats
It looks as though several dealers carry them; you might check prices on all.

My daughter had one of these for her Viszla--as you may know, that is a really short-haired breed. They are a lot more expensive now, she says, than when she got one 10 years ago!

You might also check out the Ruffwear fleece dog coat, although it doesn't appear to cover as much of the tummy.