Recently I've noticed quite alot of draft coming through the doors of my 99 e/c Silverado and being winter it's colder & windier than what we've been used to and I'd like to add something to the doors to block some or all of it off.Has anyone experimented with trying to block off the cold coming in around the door handles and what not?

I'd imagine dynomat would do what you wanting. Not 100% sure though.

R 13 would work if you could keep it clear of everything