- Buy Online! B2B About Us Support Site Map To order by phone: Inside Sales: 800.955.3729 Fax: 800.688.3729 Get a copy of our linecard ! html version printable version To the left, you'll find an area for each of the Dieterich-Post brands -- including product overviews and specifications. There is also an extensive Online purchasing site. In our B2B site you can view open orders, invoices and ...www.dieterich-post.com