If you search ARTstor with some of the suggested terms posted, you will bring up some interesting results, along with artist names.  Check the metadata attached to the image and you'll get even more ideas for terms.  
Kathryn Wayne
University of California Berkeley

Kathy Zimon wrote:

Thank you all for the phenomenal response to my query re "a term for a drawing or image made up of multiples of small images like letters, words, etc."  It seems there is no single term, but several possible ones.  Since my query prompted so  many answers, I will summarize them for the list in the next day or so.

arlis-l is an incredible reference tool.  Thanks again.
Kathy Zimon

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__________________________________________________________________
Mail submissions to [log in to unmask]
For information about joining ARLIS/NA see:
      http://www.arlisna.org/join.html
Send administrative matters (file requests, subscription requests, etc)
      to [log in to unmask]
ARLIS-L Archives and subscription maintenance:
     http://lsv.uky.edu/archives/arlis-l.html
Questions may be addressed to list owner (Judy Dyki) at: [log in to unmask]