Woodland Hills-based United Online announced this morning that it is offering its PrivatePhone and NetZero Voice phone services through Best Buy stores, as as a part of an extended marketing alliance with the retailer. United Online's PrivatePhone service offers a free phone number and voicemail for privacy reasons, and its NetZero Voice provides free computer-to-computer voice over IP calling services. Best Buy stores will be distributing demonstration and signup CDs for the services. Terms were not disclosed.