- Download the [Rules](http://drupal.org/project/rules) module
 - Enable Rules and **Rules UI**

Add a new rule 

 - **React on event**: After Saving New Content (it's listed under NODE)
 - **Restrict by type**: select your content type (ex: Article)

Under Action

 - Add Action of **Create New Entity** >> ENTITY TYPE: USER >> For your EMAIL field, Ex: **If you called your field "Email"** then it's **node:field-test**. `For user name, I guess you will also need to create a field in the node for that too. Then do same steps as e-mail`

Note: You can always click on "DATA SELECTORS" to see all the tokens you can use.

 - Add Action of **Set data value** >> select your entity ref field (Ex: **If you called your field "Test"** then it's **node:field-test)** >> for Value use **entity-created:uid**	
 - Add action of **Send Account E-mail** (listed under USER) >> Account: **entity-created** 

You can modify the e-mail templates here `admin/config/people/accounts` use tokens for your needs. 

> Let me know how this goes, I did not test this.