A tenant's utilities have been disconnected, must the land lord still file for eviction or just move their stuff out?

You can never just "move thier stuff out" you always have to go though your state approved process.

Are they still living in the house ? Have the moved out and left their property ? It can all make a difference.

If they are still living in the house you will have to evict, if they have moved away and left their property, it can be harder if they left the propety.

I just had the exact case happen here in TN. The tenant was not living in the home, the utilities had been turned off. I went down to file an eviction and they would not file it, since he was not living in the house.
So here in TN I had to either serve them notice ( which I could not do since they were not picking their mail up and no one knew where they were at) or with a witness, place a notice on their front door, giving them a 10 day notice. But your state law may be different.

MrWayne, I hope it wasn't you who turned off their utilities. That would be illegal and could fowl up your eviction plan.

Yes I did not even think of that Mr ballengerb1 is very correct, if you were funishing the utilities, you can not cut them off trying to get rid of them, They could sue you in civil court over this.