I've also been hunting coyotes for a # of years, and for the last 20 or so killed 40-70/season calling mostly. These days i've gotten away from calling, and into spot and stalk. Some of the areas i've hunted in the past that got a lot of pressure r much easier to hunt by spot and stalk. I also howl a lot for locating dogs mainly, but beware of that system, since dogs will react to it, and come in, generally slower than distress calls. Had an article once in Trapper and Predator Caller called "Finessing Coyotes", that detailed some of the methods i used to hunt. If u want send me a PM, and i'll copy it and send it to u. I've had a # of articles in T+PC that i'll send u if u want.
1 thing i'd suggest u do if you're going out on an all-dayer, is to get one of the soft-sided stadium seats that r common at Wal/K-Mart. Reinforce it with some extra closed-cell foam, cover it in burlap, and it's ready to go-- makes a long day calling out on the prairie a little less tiring, besides the fact that when tightened with the side straps, helps steady yourself for a long shot.
Always remember that howling is the ace-in-the-hole. So learn how to do it quick. Predator hunting is at an all-time high these days, and there r a lot of call-shy dogs running around out there, and learning to speak their language helps immensely.
For how-to videos i'd suggest Randy Anderson's series. For fur handling try Blaine Eddy's video "Hunting and Skinning for Profit". All this info, and other resources r easy to come by @ www.predatormasters.com