Form Field Validation in Access 2000

This is a question for all MS Access experts out there. I am looking to just make a simple form within Access 2000 that does validation based on records from a Table within the same database.

For instance, if a table had a field that listed Help Desk ticket status, such as (Urgent, Very Urgent, No Rush priority, etc.) and someone was entering the corresponding status in a Form field, and they entered an invalid status, it would give them a message warning, or other warning.

I am looking for any VB code examples that may be applicable, or directions to perform this with given steps in Access 2000.

Pointing me to a “related topic” web site would be helpful as well. Thanks.

Paul