I have Reynaud's syndrome and my hands really suffer in the cold. Here are a couple of
The little disposable packs are great: they are actually biodegradable, just vermiculite, charcoal, salt and iron. Open them to the air, and they work for 7+ hours. Local camping and outdoor shops should stock them for about $1.25 for a 2-pack. Or order from Campmor.com for $2.99 for 4.
Campmor also carries a Crazy Creek product which is a soft pocket to hold the warmer pack which uses velcro to attach at your wrist. So the warmer keeps the arteries that feed your hands warm, and your hands stay warm as a result. Works great. Costs about $7 for the pair, including 2 warming packs.
Also, I've found the most effective and thinnest glove liners to be capilene and similar high-tech camping fabrics. Ultra thin, yet much warmer than thicker knits, etc. Marmot, Patagonia and Mountain Hardware are some of the companies to make them.
Here in Durham, NC, we're in day 5 of no electricity at home due to the big ice storm that hit last Wednesday night, and brought down tons of trees onto electrical lines and transformers. So staying warm has become quite a concern! Big learning: wear a hat! Bless Polartec and their fleece.