I wonder if they ever produced a report of the findings?

I found a cached version of Tekh's journal (the link I mentioned previously that no longer works) which mentions the Grim, Boundel and Havelok stones -

http://web.archive.org/web/20090427112456/http://www.tc-lethbridge.com/tekhs_journal/?id=88

Still no information on the Immingham stone though, unless it turns out that it's the missing Grim stone.

-Chris