I've been there too!
Because not all butts are created equal you'll need to find a saddle that suits your physiology. Like Zaskar, I now use a Fizik, but I tried several saddles before I found one that really feels comfortable. I would say that a lot of my friends are now using Fizik saddles.
Then you need to get the saddle position (height, fore/aft position and tilt) set up correctly for you. A licensed cycling coach or highly experienced fitter would be the best option here, although you can do it for yourself.
Good shorts are critical and a good chamois cream - Assos Chamois Cream or Chamois Butter- make a real difference. Finally, for chafing and sore spots Bag Balm really helps the healing process.
Hope this helps!