There are none that I know of, except brokers, if you look on the load board, you would have to look for LTL loads, Call the broker, and see what EACH LOAD OFFERS. Normally the freight of the load boards are probably not what you are looking for in the way of $$$$ but figure it out and as long as it pays for your expenses to take it. I would grab it without thinking.
REMEMBER! IF YOU DO NOT HAVE YOUR OWN AUTHORITY, CORRECT
INSURANCE COVERAGE YOU WILL NOT BE ABLE TO CONTRACT THAT LOAD.
SOME COMPANIES HAVE A BACK HAUL AGREEMENT IN YOUR CONTRACT. WHICH WOULD MEAN IF YOU CAN FIND A LOAD TO TAKE YOU BACK TO YOUR STANDARD FREIGHT AREA OR CLOSE BY, THOSE LOADS NORMALLY PAY LESS THAN A BUCK A MILE, SOMEWHERE AROUND $ .65 PER MILE OR LESS.
OTHER COMPANIES WILL ALLOW YOU TO TAKE A LOAD OFF THE BOARD, THEY WANT ANYWHERE BETWEEN 10-25% OF THE LOAD FOR YOU TO USE THERE AUTHORITY AND INSURANCE.
fRANK