A.J., CARFAC Ontario
has a publication called Artists' Contracts: Agreements for Visual and Media Artists
. Although it is written specifically for artists in Ontario, it may be a usefull starting point.
With any contract, it may be good to get a lawyer to read it over to ensure everything is covered. If you use one from the publication above or find one elsewhere, it will at least save you the time and money of sitting down with a lawyer to create the first draft. If you do go with a lawyer, make sure it's one who specializes in law for artists---being in California, I'm sure you'll have a few available to you.
There are a few more resources listed at: