http://www.trailcooking.com/dehydrating101 That will get you going on the basics

Anyhow, you can dry at home nearly any bean or legume you could desire! And yes, you can use an oven as well.

You can also just cheat and buy them ready to use.... http://www.harmonyhousefoods.com/Dehydrated-Beans_c_2.html All their products are cooked and dehydrated, ready to use.

And yes, with rice, you can cook and dry rice at home so you can have more exotic types. I bake my brown rice and then dry. I use the Alton Brown Good Eats method with no oil added. Easy!!