Zanec,
Welcome to Predator Masters! You've certainly picked a lively topic for your first post. And, yes, most of us who are hard-headed enough to call lions truly need more than a little help /ubbthreads/images/graemlins/smile.gif Much of what you'll read on the topic is amusing. I find some of what's been posted here already to be as entertaining as anything I've read in many weeks.
(Personally, I've yet to call a mountain lion that came bounding to a handsqueak at full tilt from a 1/4 mile off to a just few feet from me, though numerous coyotes have responded thus over the years. With me standing in the open, no camo. In areas where mountain lions are much more common than coyotes. Yet, I'm just enough of a sucker to listen with rapt attention to what lion-mind-bending tricks others may be employing, to call them as easily as coyotes. Do tell, ChiliRojo and Pomoxis).
Several of us who are very focused on this particular pursuit--even in areas with relatively high densities of lions--can report having gone several years between detecting or sighting called ones (let alone getting a clear view). My results are about what Bearmanric said: I've called at least six for which I had good evidence in 18 years of trying. Also will mention I have yet to get a good look at a called one. About the same number I've seen in the headlights over the years.
(Might have perfected breeding and training a pack of hounds, in far less time. Q: Does SD allow dogs?).
ML typically stalk deer and elk in a wraith-like fashion. Though they're opportunistic and may respond to rabbit screams occasionally, it's probably more out of curiosity than anything else. Exceptions may be females teaching youngsters how to hunt, juvenile dispersers just establishing their own territories (often in marginal areas, particularly young males in areas of high lion density), or old lions slowed by age and infirmity whose days are numbered (Lotta chained-up goats and dogs disappear in suburban areas here due to all three of these, incidentally).
As a rule-of-thumb, the healthier and more adult the cat, the more focused on deer as prey, is the general consensus. Best bet will be fawn bleats and elk or deer calls for prey sounds. If you want to break up the boredom and call other stuff while you're waiting, a gravelly jackrabbit reeded call is a fair compromise.
If you can track one in fresh snow or find a fresh kill, you stand a better chance. Finding a kill that is a week old or less, however, can be akin to finding a needle in a haystack. I've developed a network of hikers, ranchers, biologists, etc. for this purpose.
As far as evoking a territorial response goes, I've also been using an array of lion vocalizations for a number of years now, and find they're no magic bean, either. If you're going to do this yourself, suggest using an ecaller with a remote speaker.
My stands for lions last upwards of an hour. I start with a variety of jackrabbit and deer sounds, and after half an hour or so, work up through juvie chirps to bringing in the territorial male lions, and finally mating vocalizations. (sometimes throw in an after-glow purring sequence for good measure.)
Rinse and repeat.
LionHo