Hey Lindsay
I have coeliacs disease and have been gluten free for nearly 4 years now. Michaela was gluten free for her first year to try and prevent her developing coeliacs.
To go gluten free you need to cut out wheat, rye and barley (and many people cut out oats too although recent studies have shown it's no necessary).
For our high carb foods we eat gluten free breads (I make my own or buy it - marx bakery in Auckland does a really nice gluten free loaf). Rice crackers, corn thins and corn cruskits are also cheap and easy alternatives and can be topped with the usual favs. Potato dishes are also great. You just need to be careful about the sauces and spreads you use as many have "hidden" gluten.
I'm actually about to run home for the day but will try and think of some options for you and post later. In the meantime check out
NZFSA food database this is a great resource which shows different manufactored food options for different allergies.