Seattle-based Marchex said today that it has completed its previously announced acquisition of VoiceStar. The deal was worth approximately $20M, including $12.9M in cash plus $7.1M in restricted stock. VoiceStar is a provider of pay-per-call and other call-based advertising services. Marchex said that VoiceStar will continue to operate from its headquarters in Philadelphia, PA, and as a wholly owned subsidiary of the company. Marchex announced the acquisition of VoiceStar in August.