I used quick fist clamps to mount the axe and shovel.
As for the bed extender its basically an open bottomed box made out of 1" pine lumber I had laying around, the back is sloped to account for the seats leaning back. It has a couple of cutouts on the sides to clear the cable mounts, and I attach it by strapping from the rear bed D rings up over the sides of the box and down to the tailgate latches.
I still strap bigger items, like the cooler in, buts it keeps me from having to worry about smaller stuff (come-along, chainsaw, ect) coming out when I have the kids with me.