Right now, I have saved (print & digital) the website info from the way back machine. My opponent will claim that their own archiving system is correct and the way back machine is wrong or not admissible. The info on the website would have been there for a long time, at least 6 months, so way back must have sampled it.
Domain names leave a trail too. Whois records, which servers are used, etc.
Here are a couple archival sites, I am sure there are many more.
http://www.domaintools.com/
http://toolbar.netcraft.com/site_report/
A hacker could probably get some interesting info, even without actually hacking They are probably good at finding metadata.