The macro (really close-up) pictures were taken with a Nikonos 3 with a 35mm lens and various extension tubes/framers. The strobe is a homemade mess using a small surface flash in a casing from an old Oceanic 2001 strobe. The lens was set on infinity with an aperture of f16 and a shutter speed of 1/30 sec. The "strobe" was placed an inch or so above the camera about 4" from the subject.
The other pictures were taken with an assortment of ancient (1950's/1960's) SLRs with an variety of lenses (mostly 17mm and 28mm, and the occasional 35mm ). To keep the water out, I used an older-style (1970's? 1980's?) Ikelite SLR housing with a dome port. The strobe used is mostly a Toshiba TM1 (again, old school) underwater strobe. Some pictures were taken with a small surface flash in a Ikelite housing. The lens is usually set at f11 - f16 and the shutter speed is usually 1/45 - 1/60 sec. Because of the dome port, the lens has to be focused close. Usually 6" to a foot.
March, 2007 Update: I'm now using a digital SLR (Canon Rebel XT/EOS 350D). I use it with a Zenitar 16mm fisheye lens (cropped sensor equivalent of around a 20mm lens). I put it in an old Ikelite AF housing from Ebay. I assume I'll be getting a macro lens for it as well if I can find one for less than I paid for my car.
All photos were taken by myself (Mark Hiebert) At the sites being described. All images are copyright (again by myself) and if for some reason you wish to use them, contact me and let me know. If you want to use them to sell cigarettes to children, I will probably say no.