I actually created a thread about 2WD access to Cobbler Lake a few weeks ago. I'm also keen to get up that way soon myself.
http://bushwalk.com/forum/viewtopic.php?f=37&t=11520As for the walk, not too sure how much has changed in the last 14 years or so, but from memory, the first part of the track leading from Cobbler Lake was fairly indistinct. I remember we lost the track on our way down 14 years ago or so, and ended up bushbashing towards the top of the falls, then followed the creek back to the lake.
Things may have changed though.
As for the climb, its gradual, not too steep, and well marked the majority of the way. Getting to the summit ridge is a simple effort, however to get to the true summit requires a bit of a scramble. Some might say its a piece of cake, but if you aren't great with heights, it may be a little trouble.
I found this pic courtesy of WalkWeb.net, should give you an idea of what to expect.

Either way, its a great walk, really beautiful area, why not make it a couple of days, walk to Spec, down King Spur to Koonica, across to Cobbler and back to the lake?
As for the campsite at Cobbler Lake, I cant help you here, as its been some time since I've been there myself.