Spelt is an "ancient" species of wheat. A lot of resources indicate that spelt bread and other baked goods made from spelt are tolerated by people who have wheat allergies. However, spelt contains a moderate amount of gluten and is thus not exactly an appropriate substitute. According to the Food Allergy Initiative:

Compared to wheat though, it is more easily digestible, rich in complex carbohydrates and fibre, and has a higher protein content than wheat. Some people with a wheat intolerance can tolerate spelt, but it is best AVOIDED during the initial stages of wheat free diet. If you have a wheat allergy, consult your doctor before eating spelt.

If you've determined that spelt might be a good alternative for you, here are more spelt bread recipes from Top8Free to try out. If you'd rather stay away from spelt, the Food Allergy Initiative lists other wheat alternatives that you can experiment with in your cooking, such as corn, millet, buckwheat, rice, quinoa, amaranth, tapioca, arrowroot, gram flour and lentil flour. As for bread, naturally there's rye, oats and barley.