Owen Geiger has created many house plans, and Kelly Hart has created some as well.
Kelly’s website earthbagbuilding.com has a page listing plans that are suitable for earthbag building; most of these are Owen’s. This is a good place to start.
Kelly has a site called dreamgreenhomes.com which has plans from an increasing number of green designers, including himself and Owen. Here is a page with profiles of the architects and designers and links to their plans on that site.
In addition, you can see Owen’s plans at http://earthbagplans.wordpress.com/
Over time, we plan to add plans directly to this website.