As for taking him to the vet... A snake bag and one of those instant warmers (that you put into a sock) work great! Ya know, the pocket warmer things? They come in various hour lengths and I put one into a tube sock so the snake can't be burnt by it and then throw the sock in the sack and place the snake in there too! You can then place the whole kit into a very small styrofoam cooler.
Hope this helps!