I assume my old electric tape heater thing stopped working. Not sure where my water main is located. What are steps I should do to defrost the pipes before they burst? I do have a good propane heater.

You won't know if they've already split, or burst until you defrost them. If in previous years the heat tape has prevented them from freezing, warm up the area where the tape is, and cross your fingers.

And this is why I don't support heat tape vs heat cord, foam wraps and boxing of any exposed water lines in a FREEZE Zone.

Find your waterline. Its coming out of the ground and entering your mobile home. It will not be a clean or warm job. You will not resolve your issue in minutes. It will take hours and your should remove the faucet aerators to allow debris to pass.

You might have to hire a licensed plumber now to expose the pipes, and thaw them. Next time consider Frostex Heat Cord, Foam Wrap insulation and wooden box encasement.

Best Wishes