Ubuntu 5.10 and SUSE Linux 10.0 are available for free download from www. http://ubuntu.com/download and http://www.opensuse.org/download, respectively. In either case, your best bet is to download the ISO images for the distributions from one of the mirrors listed on those pages or via BitTorrent which is what I did.
Suse 10.0 on 64-bit is very nice but I needed to add a different ethernet card since the onboard NIC was unsupported.
I'll have Ubunto in a day or so for another box.
Cheers,
Bob

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