Pancratz retired in June 2005 and the company has since been steered by Luca Majocchi, group CEO of parent company Seat Pagine Gialle.
Alexander will arrive in March after working out his notice at Carphone Warehouse's fixed line subsidiary TalkTalk. He has been managing director there since 2003.
"In a world of more and more media options and the need for advertising to generate a return, Thomson's local focus is a strong platform for businesses to communicate with interested audiences off the page and online," he said.
Prior to heading up TalkTalk, Alexander was managing director of its Mviva mobile portal.
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