Expediting Companies in Los Angeles and Surrounding Area

I am an owner operator of a Sprinter van. I used the load boards and found rather quickly that vans don't have the capacity for most of the loads offered. I joined up with an expediting company in LA and they provide a decent amount of work. I would really like to find another such company but I am having difficulty. I am particularly interested in OTR or longer distance runs to Vegas, Arizona, Oregon and other states. The money is a bit better even though the fuel costs are high. Does anyone have any tips, knowledge, or a line into such companies? I've tried Load One, Forward Air, and Landstar. They are not signing on any more Sprinter vans.