If your NIC card doesn't support PXE booting things get more interesting...

If it's a supported adapter supported by the Microsoft Windows Remote
Installation Services Boot disk and you have access to a Windows 2000
or 2003 server you could use this disk to, but the list of supported
adapters is short and doesn't include PCMCIA cards.

If you've got another laptop or the IDE adapter, you could install
using a newer computer that has a working CDROM and then transplant
the hd into the other laptop. You might have to sort out some hardware
issues with this method after transplanting.

It looks like the Linksys driver package has a DOS PCMCIA enabler
program to get the adapter to work in DOS. You could make yourself a
FreeDOS boot disk that can mount a samba share as a drive letter, then
modify the installation from Windows instructions to fit...
https://help.ubuntu.com/community/Installation/FromWindows?highlight=%28dos%29%7C%28install%29

And there are plenty of other installation hacks in the Ubuntu wiki.

https://help.ubuntu.com/community/Installation/

https://help.ubuntu.com/community/Installation/?action=fullsearch&context=180&value=installation&titlesearch=Titles

-- 
Andrew S. Zbikowski | http://andy.zibnet.us
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