Let me repost my earlier comment...

Once you join Dukhan/Sahahniya Highway.....the Exit to Zikreet old village would come at around 80Kms from Doha. Take enough food & drinks/water with you before going into the desert area. You can find some shops just before the Flyover/Exit on the left side.
Its mostly a rocky area having sand in patches.....so even a Saloon Car can make it, but an SUV (4X4) would be ideal.

Right Turn at the Flyover from Dukhan Highway to Zikreet:

25 26' 18"N
50 51' 54"E

Film City:

25 34' 41"N
50 50' 46"E