For size 6mm/1/4" and below, all taps, including bottom taps, have pointy tips.
For size 7mm/5/16" and ablove, all taps have flat bottom.
For DIE, please refer to the following link:
Die Button:
Die Nut:
Welcome to Toolingstation.
Toolingstation is Australia based supplier of taps, dies, drills, endmills, milling cutters and assorted engineering toolings and supplies (result of Google's search)