You either build your own Active Directory-equivalent from Kerberos and OpenLDAP (Active Directory basically is Kerberos and LDAP, anyway) and use a tool like Puppet (or OpenLDAP itself) for something resembling policies, or you use FreeIPA as an integrated solution.
There's also a wide range of commercially supported LDAP servers for Linux, like Red Hat Directory Server. RHDS (like 389 Server, which is the free version of RHDS) has a nice Java GUI for management of the directory. It does neither Kerberos nor policies though.
Personally, I really like the FreeIPA project and I think it has a lot of potential. I don't think there is a commercial solution based on it (anymore) though.
That said, what your are asking about is more like a fileserver solution than an authentication solution (which is what AD is). If you want your files on all machines you log into, you have to set up an NFS server and export an NFS share from your fileserver to your network. NFSv3 has IP-range based ACL's, NFSv4 would be able to do proper authentication with Kerberos and combines nicely with the authentication options I described above.
If you have Windows boxes on your network, you will want to setup a Samba server, which can share out your files to Linux and Windows boxes alike. Samba3 can also function as an NT4 style domain controller, whereas the upcoming Samba4 will be able to mimic a Windows 2003 style domain controller.