Source of microbiology related pictures

[S. D. Putnam]

Does anyone know where I can d/l some pictures (bmps, gif, jpg, etc.) or
drawings of microbiology (laboratory) based equipment, e.g. microscopes,
petri dishes, blood cells, etc.

I'm updating several training slide presentations in my lab (teach basic
lab procedures). I'm using MS PowerPoint and need to get some good
graphics/pics.  I don't have access to a quality scanner and I hate
"reinventing the wheel."  If someone has any sites/info about where I
could d/l or buy a good CD-ROM, I would appreciate it.

Thanks

SD Putnam