You will want to install Unix Support on your DCs or File Servers to run NFS.
You'll want to setup Autofs on each Linux system to automatically mount their roaming profiles.
/etc/auto.master - add this line
/home/roaming /etc/auto.roaming
Create this file
/etc/auto.roaming - add this line
* -rw,soft server:/nfs/share/path/to/users/directory& (obviously edit this line to fit your actual server shares)
Unite your Linux and Active Directory authentication
http://www.linux.com/archive/feed/40983
Fedora - AD Integration
http://forums.fedoraforum.org/showthread.php?t=216539
Yahoo Answers forum isn't the best place to ask this question... Goto Forums for help on this.
http://www.fedoraforum.org
http://www.linuxquestions.org
http://forums.ubuntu.com
You should also be aware that native LDAP on Fedora or other various linux systems can authenticate Windows but at a lower NT v4-5 level instead of the latest and greatest due to lack of support to the GPOs and other security features in Windows.
Best Regards,
Steve K. - MCITP:SA & RHCT/RHCSA