Marc's standard copyright rules
-----------------------------------
I have some info about copyright on my site. Go to:
==> Tavonni Repair Bays
==> Licencing and Other Pastimes
...and there's a bunch of stuff there. Especially read the last article entitled "FarFuture FAQ: Net Policy on Use of Role Playing Titles - 22 Jun 1998". This has more info about pictures (summary: if Marc owns it, you can use it as long as you put a copyright notice on each picture, plus include his site-wide disclaimer somewhere on your site).
Extended copyright
---------------------
You can take a read of my LibDate Copyrights page for an example. Go to my Library Data site and, at the foot of the "Introduction to Traveller Library Data" window, click on the Copyright link.
Alternatively, here's the direct link, without the LibData context:
http://members.tip.net.au/~davidjw/libdata/indexes/copy_ack.htm
For my site, Marc kindly gave me an extension on the normal rules (since the LibData is basically a reprint of the books!!!) So you may be able to ask Marc about something similar, specifically for the TravWiki site.
Hope that helps. (And in case I forgot to do it, thanks to our own Jim Vassilikos for his extensive copyright research back in the early 90's, when fans were battling TSR!!!)