2000 GMC Sonoma Stuck in a bad spot

Hello I'm writing not for advice on my truck but more my situation. I'm not sure if this is the right outlet or not but figured I would give it a shot. I took my truck in a little over a month ago to figure out why it was overheating after fixing parts of the cooling system. I was told the head was warped and decided to put a rebuilt engine in the truck. The engine they were going to put in it got sold and they decided to have my engine rebuilt. It was sent to a place and took almost 2 weeks to get it back. They put it in drove around and it was doing the same thing as before so now after a little hassle my truck is at the place that rebuilt the engine. My problem is I'm still waiting to find out whats wrong and how long it will take to fix it. I have not paid anything but being without a ride is a big hassle. I don't know how to handle this situation as I've paid nothing and nothing is in writing. I'd atleast like a rental. Any helpful information would be appreciated. Thanks