Yep, I know **exactly** what it's like Both my hands and feet (mainly my hands) are always freezing! I too have very bad circulation and so unless it's stupidly hot outside my hands are purple (as well as a variety of other interesting colours! lol).
One thing I do find really helps loads is wearing a pair of cotton fingerless gloves as often as possible. I know it may sound stupid but it really works! Cotton is the key as it produces warmth in your hands very quickly and if you wear gloves lots you'll find that your hands will be so toasty warm they'll be sweating!
I've found that I've gotten into a habbit of everytime I head outside I've got them on and I leave them on for a little bit once I get back inside...but when I take them off my hands are always lovely and warm
Hope that helps! Best of luck