The March 28, 1938 issue of LIFE Magazine carried an article entitled “Americans Have Died For Democracy in Spain” (pp. 56-67). In preperation for the article LIFE photographer, Peter Stackpole, took several photographs of returned volunteers. These photographs are now on the web: Aaron Harris, Doug Roach, Hy Roseman, William Harvey (Herrick), Morris Fishman, Robert Klonsky and Ruby Ehrlich. These photographs can be found online under LIFE images. Two were unidentified and I have now (10 Oct. 2009) identified them as Philip Haydock and Hy Stone. The men who appeared in the article that who’s photographs are not online include Max Katz, Nils Berg, Frederick I. Lord and Jerry Warren. I would like to get a good scan of the article I have a photocopy.
A complete listing of LIFE articles dealing with Spain is posted by the University of Texas at Austin here.