Both Dominos and Eagle Boys give the option of a gluten free base - just make sure you have a look at what sauces and toppings have gluten in them.
Almost all of the sauces at Fit Chips are gluten free (with clear labelling, so you'll know which ones to stay away from).
Muffin Break have a wide range of yummy gluten free muffins.
The Cookie Man has (at the time of posting) Milk Chocolate Chunk and White Choc, Macadamia & Apricot gluten free cookies.
At Nando's all the chicken breasts, legs, steaks and tenderloins are gluten free. Also, all the salads with trio of bell peppers dressing, rice and corn on the cob are gluten free. You can choose to replace a chicken meal's serving of chips with rice to make it GF.
Mexican and Indian are relatively safe restaurants to visit, so long as you stay away from flour tortillas and the breads/pastries. Almost every Indian restaurant I have visited have used gluten free thickeners in their meals, but just check. As with Mexican, corn tortillas are gluten free so there's a fair amount of choice (although you might want to confirm).
I'm not the biggest fast food fan, but when my friends are endulging it sucks to be left out, so...
McDonalds: the chips and hash browns, honey mustard, tomato sauce & ranch sauces, garden salad with italian dressing, and all drinks EXCEPT iced coffee are gluten free.
McCafe: Chocolate and raspberry friands, GF triple choc fudge cookies, GF white choc chunk & macadamia cookies, almond and orange loaf are gluten free. Beware of the drinks there because a lot have gluten in them (incl. soy milk) so your best option is a coffee or black tea.
Hungry Jacks: the chips and hash browns, garden salad with french dressing and all sundaes (only in WA) are gluten free. If you can be bothered stressing that a burger must be freshly created without ever touching a bun, then all the burgers except for the Angus and Vegie Burgers will be gluten free.
Chicken Treat: only the coleslaw, peas, roast potatoes and corn cobettes are gluten free. I can only assume Red Rooster is much the same.
KFC: Nothing is gluten free.
And the most important place in my opinion (although no longer with the Whitford City store)... Alternative Bites in Garden City. Everything is gluten free - breads, sausage rolls, pies, muffins, cakes, pizza bases, quiches, buns etc - and is really yummy. Since I live so far away from there, I just order it all frozen and stock up.