Some relevant links;
JMC Scientific Consulting (my scientific consulting company)
International Society for Diatom Research (society promoting diatom research and membership gives access to the journal Diatom Research)
Royal Microscopical Society homepage
Quekett Micrcoscopical Club (excellent historical microscopy club, and publishers of the Quekett Journal of Microscopy)
Postal Microscopical Society (another great microscopical club, and publishers of the Balsam Post)
Microscopist.net (loads of information about historical microscope slide makers)
World Register of Marine Species (one of the great online resources for checking diatom naming)
MaxMax (where I got my monochrome converted cameras from)
Zerene Stacker (image stacking software)