Lync Server’s Enterprise Voice feature aims to enable you to replace your PBX. Enterprise voice helps you to get your users to use either a soft phone, the Lync client, or replace their existing desk phone with a Lync Phone.
Lync Phones are full IP phones – they contain some sort of computer and OS that either runs the Lync Phone Edition client or runs a compatible client. Both modes enable the phone to participate fully in your Lync environment.
One of the bigger players in the VOIP and Lync market is snom, and they’ve just produced a simple free eBook entitled: Using Microsoft Lync with Voice and snom Lync Qualified Phones. This is a 4 chapter book that covers an overview of Lync Phones, how to provision and customise Lync phones and how to integrate PC/Phone and Lync.
The eBook is free, but to get it you must first register with snom, which you can do on their website. The book itself is here.
The book is a good introduction to the Lync Phone even if you choose not to use snom phones.