samba - Apr 2005 - New list user, couple of questions and looking for existing examples

I'm a new list subscriber with a couple of questions:

I have a few objectives with samba that I think can be accomplished.  If I
am wrong, someone please indicate my errors before I go a long way down a
dead end path.

I need to put all of my PC users home directories onto a samba share so
centralized backups can be done to capture email, docs, etc.  These are all
WinXP Pro boxes.  We use a work-group, and not a windows domain.

I need to ensure that those users files are accessible by only those users.
It appears that this means I need each user to have a Linux user account on the
samba server.  Is this correct?

I need some groups of users to have a shared pool of r/w files, that other 
group(s) cannot access.  I assume this requires using Linux group, correct?
 
Do my above re1uirements mean I need to learn about and implement LDAP, or is 
there a simpler solution?

None of the printers and plotters is on a Linux box, they are all attached
to WinXP machines.  I believe I can still use Linux/samba as a print server
in some fashion??

Is there a general "examples of ..." available, besides the samba FAQ?

Is there a search-able list archive (if so, where)?

thanks in advance,
-chuck