Finding, to purchase, quality NEW color 35mm slides on art Histoty
between the time perids of 1300 to 1900 to use in lecturing. I am
looking for a domestic site but an International site is fine if I am
able to order and can communicate with the language barrier. I need
this as soon as possible. Thank you

There are extraordinary visual resources available from some museums.
You can contact them individually or, better yet if your library or
school has a membership, AMICO, the Art Museum Image Consortium, is a
collaboration of museums to make images of their art available. You
would be working with digital images instead of transparencies. Many
classroom projectors now are data projectors that connect to computors
or laptops so storage and presentation of media is easy. Unlike
transparencies, the digital images won't degrade over time and with
use.

One of my favorite free resources of art transparencies and digital
media is the National Gallery:
http://www.nga.gov/education/classroom/loanfinder/

I haven't answered your question, but I hope I have given you some ideas.

I'm sure this is an oversimplified answer, but www.artslides.com has
comprehensive sets that can be ordered depending on the time
period/area of interest but also based on the text you are using for
lecture (if applicable.)  It's not cheap at $2.50 a slide (for larger
sets,) but the site provides the a comprehensive list of images for
each section in case you feel inclined to fill your own set elsewhere.
 And if you are using a text and your school is paying,publishers
sometime provide the supplemental slides (at a price.)

Personally I prefer the digital projection, as well - there's no more
slide sorting, it's easy to pull up images individually, and for
contemporary art it's much easier to keep up with the times {even
Prentice Hall has coverted Janson's slide set to Powerpoint
http://vig.prenhall.com/catalog/academic/product/0,1144,0138884544,00.html
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