Good quality high speed steel or Tungsten Carbide are the only drills worth buying for serious drilling of anything tougher than mild steel. Try shopping with Victor Machinery Company.
www.victornet.com I've been buying drills, milling cutters, and other tooling from them for several years. Their prices are reasonable, and they have several different choices of drill bits available, including some very high quality USA-made stuff.
The trick to drilling tough metal is to use the right speed, feed rate, and lubricant. Once a drill starts to "skate" without producing chips, it dulls quickly.
Jerry
