It couldn't hurt to just ask. She'd probably be flattered that you're considerate enough to provide something appropriate for her. Or you could look online, perhaps AllRecipes.com. They seem to have everything! Or even About.com, who also seem to have everything.
Other than that, I'm not informed enough, either, to know just what limitations diabetics have.

Redvixen, thanks. Yeah, I will ask but still would like some basic knowledge. I know absolutely nothing about it. I started reading the wikipedia page and my eyes started to glaze over.

Just to be clear: I'm not looking for recipes at all as I've got a gazillion. I just need to know what not to gather into the desserts.

I am almost positive that anything that is a natural sugar is out. Artificial sweeteners are the only way to go, and that probably means avoiding lots of fruit too, as they are loaded with natural sugars.

Of course, this could just be male answer syndrome rearing its head, as I am not a dietitian!

dobbs, short answer from someone who works with an insulin-dependent diabetic: Use. Splenda.

beyond that, google 'glycemic index recipes' that'll help you out.

all natural sugars are pretty much out of the question, meaning honey, agave nectar and maple syrup included.

dobbs, I have diabetes.

Yes, a diabetic should avoid most "real" sugar (honey, syrup, etc.). There is an alternative - you can buy Splenda in a version that equals (ha!) sugar. Meaning one cup of Splenda will equal one cup of sugar. I've never cooked with it myself but it's supposed to work well. I don't know if it will work with whatever dessert you have in mind - read the box.

All fruit is not created equal. Berries are better than citrus fruits for instance. Berries metabolize more slowly and lessen the sugar spike.

Part of the problem is that not all diabetics are the same. We all handle carbs (fruit, desserts, starches) differently. For example: most diabetics avoid bananas; I don't have much problem with them.

Feel free to email me.

Hmm. Okay, thanks for the answers, especially deborah.

I will call the client back and get super clarification and if it's serious (no fruit, no natural sweetener), I'll back out of the event. I'm sure she wasn't expecting Splenda in the dessert and there's no way in hell I'll make something with that in it--isn't it today's version of Aspartame?

The client came to me because I make raw/vegan desserts--I'm sure when she asked she assumed I knew enough about diabetes to answer her question properly. When she said "Can you make something for diabetics?", I assumed she meant, "Can you make your raw, vegan desserts for diabetics?" Without some natural sweetener, I can't pull that off unless she wants a very tart Lime Mousse Tart or something.

Thanks, all!

And... after posting I realize even a tart Lime tart is out as it's got.... you guessed it: LIME in it! ;)

I've never used it myself and don't really know anything about it, but couldn't you use stevia?

Stevia is what my cousin uses. I grew a stevia bush and harvested the leaves, and it really is great. Just a pinch will do.

However, dobbs, Splenda is the brand name for sucralose, which as the name implies is made from sugar. It's not quite all-natural, but it's not a completely synthetic chemical like aspartame.

Thanks for the additional comments. I've left a message for the client to call me to discuss.

I've used Stevia in a number of desserts but all of them are citrus-based like the lime mousse tart.

I'll see what I can get from the client.

I'm actually kind of interested in the answer, dobbs, if you feel like posting an update once you have more information.

Actually, I've used Splenda, though not in cooking, in my coffee, and it tasted the same to me. I've heard good things about it, except it's expensive.