As Technet Gallery is retiring so moving the code to Git Hub. (click below github download link for this script)
There are many methods to extract data from Active directory for example:- csvde , vbscript etc..
I have created a script using Quest management shell & excel to extract the attributes from AD directly in to excel file.
No need of formating or importing CSV to excel file as this will do all the work for you.
Note:- I have commented sizelimit 0 so as to see the output of first 1000 users, you can remove it so that all users can be exported.
Also, I have used extnsionattribute1 to extract some custom values, you can change that accordingly.
running from c:\scripts
Pls rate the contribution if it worked for you.
download Quest Management Shell (its a free shell) –> http://www.quest.com/powershell/activeroles-server.aspx