Personally, I use a clothing iron and just wrap the bottom with tinfoil. Toy with the temperature and it works perfectly.
dude! that's a great idea! why didn't I think of that! i've been using a clothing iron since i started waxing cause it was only $5 at a local used item shop..wanted to save up for a fancy iron to get the even heat distribution (mine has holes for steam) but I'll give this a try first!