If you cannot see the names in the AD you need to do this :
http://blog.schertz.name/2010/09/updating-the-lync-2010-address-book/
Update Clients
Just as Office Communicator has done since a later R2 hotfix, Lync also will not immediately download changes to the Address Book files when first launched, but instead wait for a random interval of time between 1 and 60 minutes. To trigger an immediate download two steps must be taken on the client workstation. The first step only needs to be performed once per workstation, while the second would be done each time a forced update is desired.
- First, execute the following command from the Windows Command Prompt run as an administrator (or manually add the GalDownloadInitialDelay registry key). Setting this value to 0 will force Lync to immediately download the address book instead of randomly selecting a time to check the server.
reg add HKLM\Software\Policies\Microsoft\Communicator /v GalDownloadInitialDelay /t REG_DWORD /d 0 /f
Take note that the there is another difference here between the Lync and Communicator clients. For standard 32-bit operating systems the registry path below is the same regardless of the client versions (OC 2007 R2 with July 2009 update or Lync 2010 RC) but previously 64-bit operating systems running the 32-bit only OC 2007 R2 client had to have the setting created under the Wow6432Node policies key.
- Second, exit the Lync client and manually delete the GalContacts.db and GalContacts.db.idx files from the user’s profile directory. If the .db file still exists during startup of the client then Lync may still wait for that random interval between 0 and 60 minutes before checking for changes on the server’s address book files. By deleting the file the Lync client must download an entire new copy, forcing it to pick up any changes.
On Windows XP workstations:
%userprofile%\Local Settings\Application Data\Microsoft\Communicator\sip_<username@domain>\
On Windows Vista or Windows 7 workstations:
%userprofile%\AppData\Local\Microsoft\Communicator\sip_<username@domain>\
- Restart the Lync client and search for any of the recently changed information, for example the Telephone Number added to this AD user account now appears for the Lync contact.