I love my book entitled Charming Handmade Clay Crafts. It has a section on making buttons. You can buy a used copy of the book at Amazon.com for $4.50. I buy used books through Amazon all the time and typically the books look brand new. I seriously just bought a Pricilla Houser painting book for 76 cents LOL. It was brand new... didn't look as if anyone had even thumbed through the pages.

Molds are so easy to make. There are numerous products available depending on your needs.

I've used polymer clay to make molds. Just press the original button into the clay... remove it... and bake the polymer mold according to the package directions. It's a no brainer.

For some designs it's necessary to use a flexible mold. For those I use liquid latex. You simply paint the original with it, let it dry, paint it again with a few thick layers. And when it's thoroughly dry it's a nice rubber mold. A flexible mold is good for raised designs that have undercuts. Like a button that has little flower petals and leaves that are 3 dimensional. I bought mine at Home Depot.

Home Depot has a product called Mold Builder liquid latex rubber. I just found it on the Delvie's Plastics Inc., website.

Here is a link that might be useful: liquid latex