The Gerbing stuff gets good press - if a little expensive.
I considered getting some and possibly socks too.
I don't stop riding if it's cold but cold extremities can distract from concentrating on the job in hand (and no that's not another cold extrimity!

)
I tried 'Coldkiller' glove liners but they're awkward under my Triumph Sympatex gloves - too bulky - and, for me, they didn't work too well anyway.
Anything is worth considering if it means continued riding.