I've recently written a series of posts on the process of automating the unit testing of CRUD operations on business objects.
In future posts I'll dive into some of the details which I didn't go into such as how to set the allowable values for a property, how to ignore a property when comparing objects, how to set a property value as unique, as well as how to manage relationships among objects. Look for a zip file containing a running example in the next couple of days.