If you don't already have one , get a good spotting scope and IMHO binoculars should be 10x42. Depending on the amount of pressure the antelope recieve on the land you're going to hunt will a bearing on how hard you will have to work. The more you view the better you'll get in judging an animal and knowing which one is worth a stalk or shot.
Like in any hunting getting familiar with the terrain goes a long way in a successful hunt. If you've been a good whitetail hunter over the years you're going to find antelope fairly easy. The name of the game here is patience. A little hint , I've found antelope a creature of habit and predictable and easily ambushed if you are willing to get up early, do some hiking and be set up 45 minutes or so before sunrise.
Any rifle you're capable of shooting well does the trick. A properly place shot from most any caliber will drop a speed goat in it's tracks. 270,280, 25-06,308, 30-06 or any 7mm are good choices and odds are you probably own one or more already.
Good luck and enjoy antelope hunting! They are my favorite big game animal to hunt.