yea there isnt really any gud websites, try to get a book on shipwrecks... surfing chemistry ; shipwrecks and salvage is a good one...dont really know where you can get more info..but the net is not very useful
http://www.anmm.gov.au/anchors&cannon.htm ... there's the maritime museum site, which may help you a bit when looking at the restoration and conservation of artefacts..