Same calls that work for coyotes, will work for bobcats. Take a look at the tracks in the area, and use those kind of calls. I have had them come into all the same calls. Switch up your calls as you are on stand. I start with a jackrabbit normally, cycle into a cottontail call, then into a bird like a woodpecker or redbird, then into a higher pitched cottontail such as a baby cottontail. A bigger issue is location. They like the brush and rocks, head for that. I will set up along canyons, and thickets, and call parallel to them. I put my caller out 40 yards ahead of me, and at a slight angle. This way if they try to slide in beside me or in from the rear they are done. I spend about 12 minutes on stand, if you are going just for bobcats, you might stay a little longer, but try to cover as much ground as you can to improve your odds.
Good luck,
Mo