Instructions for Eclipse Indigo:
Once installed click on Window -> Show View -> Others. A new window pops up. Click on folder Hibernate and select Hibernate Configurations to setup a DB connection. It is possible to setup a new connection using an existing Hiberbate properties file or creating a JDBC connection.
Once setup your DB connection click on Ping to test everything is correct.
Lastly, click on the Open HQL Editor button (third button on the top Hibernate Configurations menu) to run a HQL query.