Elizabeth, this response might be coming way too late for you, but I stumbled across this thread while looking for a particualr topic.
Yes, you can make slides from digital images. I found
http://www.slides.com located in Wisconsin and ordered through them with great results.
The first slide was priced at $4.00, 2nd at $2.00, 3rd at #1.50, 4th at $1.00 plus US priority mail at $5 to California.
If you know of one better priced by now, please share the address.