The Extreme Wheelers 4 Christ map is pretty good. If you use Google Earth you can check out the area and get the coordinantes of any spot you want. Look for Boone Rd off of Hwy 247/Old Woman Springs Rd in Johnson Valley. Boone Rd turns north from the hwy and goes about 4 miles to the dry lake bed. On Google Earth you can see RV's on the lake bed so you know the area we'd be in. If you search for Johnson Valley it will take you to a spot a few miles west of Means Dry Lake, so zoom out and look east to Boone Rd and the lake bed. You'll have to zoom in before the street names show up, they're dirt roads.
Really, finding your way is easy, once you turn on Boone Rd you just stay on the main road and drive to the lake bed, nothing confusing about it.