I've tried lots of different gloves though not all of the types of gloves people have recommended. There are so many kinds! So far, the best gloves for me are super-thin ski mittens. They are thin enough that I have a lot of dexterity. They are very roomy, and I wiggle my fingers in them as I ride to generate heat.
I would never have ordered these online the first time. I found them at Campmor. Then I lost one, so I ordered a second pair.
Gordini Men's Stash Lite Touch Mitts, $30