The Telerik Data Access Data services work like the regular services, so you should place you example code in the same class. As those classes are generated by the wizard the right place for you custom code is in a partial class.
Please make sure that your partial class is with the same namespace with the one generated by the wizard.
I hope this helps. Should you have any further questions do not hesitate to get back to us.
OpenAccess ORM is now Telerik Data Access
. For more information on the new names, please, check out the Telerik Product Map