Contact the Defenfense Logistics Agency (DLA) Law Enforcement Support Office (LESO).
https://www.dispositionservices.dla.mil/rtd03/leso/index.shtml
They will be able to tell the agency who the State Coordinator is. This person usually is an employee of the State that the LE agency is located in and will probablt work for the Department of Public Safety or Attorney General's Office....or similar agency in that State.
The State Coordinator can obtain an agency ID number for whoever will be responsible to screen the items. They will be able to sign on to a website with that ID that is similar to the Government Liquidation site. You can view the items available, which is not limited to vehicles, and submit for approval any items that you want.
The only bad part is that there are not always pictures on the website of the vehicles. If you are close enough to where the vehicles are located, i.e. a DLA storage facility, you can ask for permission to go there and screen the items in person with a 48hr advance notice. If there is something you want, record the DTID number and you can locate it on the website by researching that number and submit it for approval.