I need to begin making desserts that have NO WHEAT FLOUR in them.
I have never worked with replacing them with other flours before so I'm curious... what other flours can I use as a 1 to 1 replacement? Or is that not possible? Do I need to mix other flours to create something that works?
I want to be able to make cakes, cookies, tarts, etc.
Why do you need to give up flour? Is it because of a sensitivity to wheat or gluten or because you are trying to eat healthier? Gluten is the protein that develops and helps baked goods rise. Wheat flour is rich in gluten, while others hardly have any (that's why a spelt or kamut breat won't rise properly - I learned that the hard (litteraly!) way!)
So, if you can tolerate gluten but have to stay away from wheat flour (that happens), you probably could add vital gluten to your recipes (it is sold in natural food stores).
If you cannot and have to use other flours, then you have to experiment (and ruin a few recipes in the process).
Because they do not rise as much as cakes, cookies are easier to make (they will be more chewy and less scrumptious, but still edible).
Looking up recipes in a vegetarian cooking website (see link below) or borrowing books on the subject at your local library will probably be very helpful.
I have a family member with a gluten intolerance. She's not a big sweet eater so we've never really rolled up our sleeves to try and convert wheat flour recipes to non-gluten recipes. Instead, we've gone the "non-flour" route and found lots of great options. Search the web for flourless chocolate cake recipes. Also, meringue cookies and cakes are a great option. Check also for celiac recipes as you will find some stuff there (though some will be non-wheat but not necessarily non-gluten).
Here is a link for "chocolate sparkle cookies" - these were created by Thomas Haas, a spectacular baker who works at Sen5es in Vancouver. So easy to bake and sooo good.
If you're cooking for these folks regularly, invest in a cookbook like my favorite, "Fabulous and Flourless, (or vice versa?)" for a host of nut-flour cakes, cookies, puddings, and other desserts.
If you want to make "regular" desserts, my celiac grandmother and gluten intolerant self made do with a baking mix of 1/3 rice flour, 1/3 soy flour, 1/3 potato flour for each cup of wheat flour called for in a recipe. I use this mix to flour cake pans when I make nut flour desserts. There are a lot of gluten free bake mixes out there, too, often in the natural foods aisle.
Don't rule out roasted fruit, served it with toasted nuts and honey, or sliced fruit served with cheese.