Westlake Village-based ValueClick said Friday that CEO Tom A. Vadnais is retiring from the firm, and also resigning as a board member. Vadnais is being replaced by James R. Zarley, who was most recently executive Chairman at the firm. Vadnais has been CEO of ValueClick since May of 2007, and was the initial angel investor in the firm. Vadnais is also being replaced on the baord, by Martin T. Hart.