I have a model with a latex allergy: what are my other options?
If your models cannot be in contact with latex you can use alternatives. Since Latex comes in many forms it's not entirely clear which form you're using but I assume you're mainly referring to latex prosthetics.

Latex

I think the most common alternative would be to use silicone. Silicone is a man-made alternative to the more natural latex, and it generally ages better so silicone appliances can be stored and used later and will keep better than a latex appliance.

Liquid Latex

If you're looking for alternatives to liquid latex, you can use Elmer's Glue or spirit gum if you're using it as an adhesive.

I also found this cool site which shows you how to make a faux version of latex from home which considering your amateur nature may be appealing.

http://www.diypics.com/how-make-latex-fx-makeup/