who or where do you sell them?
There are traveling antler buyers in most states. We have a ton of buyers out west, but shop around prices, the serious guys pay way more. It also helps prices if you have a lot to sale. My buddies and I will sale to the same buyer at the same time to increase what he will give.
Once the antler turns white at all the price goes way down. Brown is the top grade, then hard white ($4-7 per pound) then white cracked $2/ pound ish, and then and the lowest grade is called Chalk which is not worth $0.50 a pound. Buyers won't take antlers that are flaking and breaking.
Deer are worth about the same amount per pound but weigh a lot less than an elk's antlers. If you find a very large set they will pay a premium. I have a few sets that could bring $500 plus. Giant sets have sold for tens of thousands.
The antlers are used for art, sold as dog chews, but most are ground up and shipped to Asia for "health food" additives and vodo medicines. The are just bones, but 2 billion people think they have some sort of benefit or power so they are worth a lot. In Asia antler can bring 10X in the right market com paired to what we get here. Sheds are renewable but sadly the value does increase poaching.
It is really fun but it is so competitive around here. Guys watch the deer and elk really closely and when one sheds guys end up in a foot race. This spooks the animals and is stupid as the animals are stressed from snow and cold already. I hunt areas you can't see from any road. You have to hunt in secret spots and hike a long way. States are now starting to regulate antler hunting. In Utah you have to pass a test and carry a permit with you to pick them up. In Wyoming you can't touch an antler until I think May 1st or you will be arrested. Montana has opening dates for different areas. The wardens plant antlers with gps trackers in them in areas guys cheat. They then just go to the house where the signal is coming from and take the guy to jail.
My best day was $1350 worth of elk a long time ago, and I had to leave many sheds behind. We make cashes of the lesser ones and then go back to get them latter.
I just like the feeling when you find something. Golf balls, antlers, fish, arrowheads, crusty zinkons, pull tabs, 1997 Shasta cans down 13 inches, can slaw, extra. I love archery hunting best of all though.