Depends on the course. I paid $800 for a class last year, plus airfare, hotel, rental car, and 500 rounds of .45. However, it was a five day course, with instructors I had wanted to meet, in a state I like to visit - so I did not view it as unreasonable.
On the inexpensive side, an arbitraty $350 pistol; for argument's sake three magazines; a Simply Rugged belt, holster, mag pouch set; 1000 rounds 9mm range ammo and 100 rounds HST or Ranger T from an online source; and a decent one day class... would be around $1100. Of course, that doesn't incude range fees for solo time, or a wardrobe upgrade.