Unfortunately there aren't many places they can be let off lead (your dog, I meant, not MN or MT;-p)

If you go to this Facebook link https://www.facebook.com/#!/groups/174477659275888/

they should be able to give you much better ideas of where to walk your dog off lead.

As Mandi said, most people buy their supplies at the vets. Also on Facebook, search Qatar Vet Centre and Parkview Pet Centre for all your pet needs:-)