Many of the books on the Translations page also have good information on collaborative piano.
Adler, Kurt. The Art of Accompanying and Coaching. Minneapolis: University of Minnesota Press, 1965. ML 417 .M85 A3
Emmons, Shirlee. The Art of the Song Recital. New York: Schirmer Books, 1979. MT 892 .E54
Katz, Martin. The Complete Collaborator: The Pianist as Partner. Oxford ; New York: Oxford University Press, 2009. MT 236 .K27 2009
McTyre, Ruthann Boles. Library Resources for Singers, Coaches, and Accompanists: An Annotated Bibliography, 1970-1997. Music Reference Collection no. 71. Westport, Conn: Greenwood Press, 1998. ML128.V7 M45 1998
Moore, Gerald. Am I Too Loud, a Musical Autobiography. New York: Macmillan, 1962. ML417.M85 A3
---. The Unashamed Accompanist. London : New York: J. MacRae ; F. Watts, 1984. MT 68 .M6 1984
Price, Deon Nielsen. Accompanying Skills for Pianists. Culver City, Calif: Culver Crest Publications, 1991. MT 233 .P76 1991
---. Accompanying Skills for Pianists: Including Sightplay with Skillful Eyes. 2nd ed. Culver City, Calif: Culver Crest Publications, 2005. MT 236 .P75 A2 2005
Spillman, Robert. The Art of Accompanying: Master Lessons from the Repertoire. New York: Schirmer, 1985. MT 68 .S7 1985