This has got to be the easiest way I can ask any of you how to do what I want.

You see this?
http://ltsp.org/images/ltsp_diagram.gif

I want to do this:
http://img227.imageshack.us/img227/2...iagram2am1.gif

How do I do it?
If I understand correctly, LTSP is limited by the boot process.

If that's true, is there a way I can create a remote XDM login via Internet connection to a host server? How? I can't find any straightforward things about this throughout the vast documentation I come across.

what is your problem.... ? if you don't use a switch then don't use one...
the rest is wonderful and I mean wonderful explained at ltsp.org
TFTP Server, DHCP and the rest that has been mentioned there.
Infact that you want to boot trough the internet I wonder which bandwidth you've got...
Nothing is impossible but you'll have to configure a lot regarding hosts cause if the clients have no fixed ip thats what I guess, they must be recognized in a way for the ltsp that it can recognize it but I yet don't know how.
Must be something like that:
http://dragonwall.net/xdeep-putty.html

Here's the problem. LTSP clients don't have a hard disk--they use DHCP to find a server to boot from. That means they broadcast a request to any server that's listening.

But DHCP broadcasts aren't transmitted to the internet. I don't believe there is any way to forward DHCP broadcasts to your particular server.

The solution (I think) is to install a small hard disk and a rudimentary GNU/Linux install and then use remote login to access your remote machine.