This post is over a year old, some of this information may be out of
date.
Backbone-form https://github.com/powmedia/backbone-forms
This is the simplest tutorial I can find for Backbone.Marionette http://davidsulc.com/blog/2012/04/15/a-simple-backbone-marionette-tutorial/
Backbone.Marionette Boilerplate (hope somebody may find it useful) https://github.com/snovos/backbone-marionette-boilerplate