Best areas, that are on public land, usually require preference points. You can earn one per year. We have many units that have a over the counter bull tag but the legal bulls are usually few and far between. If you have horses and are willing to pack in 5-10 miles you might find some bulls.
http://www.wildlife.state.co.us is a good place to start looking. They have most of the info you'll need to find the better areas. Go to hunting, big game, statistics and look at the harvest reports, draw odds and unit info.
What makes for a good area to hunt for you? High success? Lots of elk? Few people? Trophy quality? You can have some combination of two or three of these things in unlimited areas, but not all 4. The only way to have all of those things is in a trophy unit.
And of course, coming right out and asking where the best place to hunt with an unlimited tag isn't going to get many responses. We may spend our whole lives looking for that "best" place and never find it. And those who did find a great area would probably like to keep it to themselves.
Over the years I have seen several elk and deer hides left in the woods by hunters and I have to wonder why they do this? I fully understand and agree about getting the hide off the animal as soon as possible to cool the meat, but why not pack out the hide with you and use it? As far as I know there are no state laws that require you to take the hide home, but to me why waste such a beautiful part of the animal? Some might think they have no use for the hide or it costs too much to tan....