You should go to a hardware store and get a glass bit, dont use a normal drill bit. Second when your drilling make sure you put something around your face/nose area so you dont inhale the glass dust that comes when you drill. Third you CANNOT move the drill around it has to stay steady while drilling or you will crack your hole. Fourth you need to drill it in pulses so it does not get hot, do 20-30 second pulses.

Id go to a hardware store and find a metal tube first so you know how big a hole to drill, use the tub for your stem. As for a bowl piece I used a socket from a socket wrench and welded mine on there, works great. I used a gentlemen jacks bottle and its a sweet piece now. I dont know what you would want to use for a solid bowl piece but you can figure that out after your done.... Good luck!