The orchestral score
Scanned (large) Indiana University
Scanned (small) Indiana University
PDF Free Sheetmusic Library
Online Discographies. Each of these discographies is either fairly complete or contains useful critical commentary. (The latter are marked with an asterisk.) Because some are embedded in larger sites, I've generally linked directly to the 'Beethoven' page where one exists. Sites which appear out-of-date have their posted date of last revision in brackets.

Note: I can't read Japanese, but I've been able to get quite a lot out of the Japanese sites using Babelfish.

Conductors
Claudio Abbado
Karl Böhm
Sergiu Celibidache [1999]
Ferenc Fricsay
Wilhelm Furtwängler*
Wilhelm Furtwängler
Roy Goodman
Gunther Herbig
Jascha Horenstein* [2001]
Jascha Horenstein [1996]
Herbert Kegel
Erich Kleiber
Otto Klemperer [2002]
Paul Kletzki
Hans Knappertsbusch [2002]
Josef Krips
Rafael Kubelik [2002]
Willem Mengelberg* [2002]
Willem Mengelberg [2002]
Yevgeni Mravinsky [1999]
Eugene Ormandy
Heinz Rögner
Kurt Sanderling
Jaap Schröder [2001]
Carl Schuricht [2000]
Georg Solti
Leopold Stokowski
Leopold Stokowski*
Klaus Tennstedt [2001]
Klaus Tennstedt [2002]
Arturo Toscanini [2002]
Bruno Walter
Ensembles
Academy of Ancient Music
Northern Sinfonia
Vienna Philharmonic
Labelography
Command Classics
Other discographies
Eroica (Deryk Barker)
Eroica (Satoshi Konno)
Opus 111
Other Composers
Bach, Goldberg Variations
Berg, Violin Concerto
Brahms, Symphonies [2001]
Bruckner, Symphonies
Bruckner, Symphony #8
Hartmann [2002]
Mahler
Pärt
Pettersson [2001]
Scelsi
Schoenberg [2002]
Other Conductors
Karel Ancerl
Clemens Krauss
Other
Henry Fogel's collection
Of related interest
John Hunt Discographies
Bibliography
Adorno, Theodor W.1993 Beethoven: The Philosophy of Music (Fragments and Texts).
Ed. Rolf Tiedemann, tr. Edmund Jephcott. Stanford: Stanford University Press.
Bowen, Jose2001 Bibliography of Performance Analysis.
1996 Tempo, Duration and Flexibility: Techniques in the Analysis of Performance.
Journal of Musicological Research, Vol. 16, No. 2 (July 1996).
1993 A Computer-Aided Study of Conducting
Computing in Musicology, Volume IX.
Burnham, Scott1995 Beethoven Hero. Princeton: Princeton University Press.
Day, Timothy2000 A Century of Recorded Music: Listening to Musical History. New Haven: Yale University Press.
Epstein, David1994 Shaping Time: Music, the Brain, and Performance. New York: Schirmer Books
Grove, George1898 Beethoven and His Nine Symphonies. Third Edition. New York: Dover Publications (1962)
Hudson, Richard1994 Stolen Time: the History of Tempo Rubato. Oxford: Clarendon Press.
Kolisch, Rudolf1942 Tempo and Character in Beethoven's Music
Musical Quarterly, Vol 29, 2/3.
Lumpe, Ernst A.1990 Pseudonymous Performers on Early LP Records: Rumors, Facts, & Finds. (rev. 1999)
ARSC Journal, Vol. 21, No. 2
1996 Pseudonymous Performers on Early LP Records: an Update.
ARSC Journal, Vol. 27, No. 1.
2002 The Royale pages.
Nettheim, Nigel2001 A Musical Microscope Applied to the Piano Playing of Vladimir de Pachmann
1997 A Bibliography of Statistical Applications in Musicology.
Musicology Australia, Vol. 20, 1997, pp. 94-106.
Senner, Wallace, and Meredith 1999 The Critical Reception of Beethoven's Compositions by His German Contemporaries
(North American Beethoven Studies, V. 3.)
Sipe, Thomas1998 Beethoven: Eroica Symphony. Cambridge: Cambridge University Press.
Solomon, Maynard1977 Beethoven. New York: Schirmer Books.
Taruskin, Richard1995 Text & Act: Essays on Music and Performance. Oxford University Press.
Wallerstein, Edward1976 The Development of the LP.
High Fidelity, April 1976, Volume 26, Number 4.
Yoshii, Satori2001 [Eroica Discography]
Classic Press 6/7.
Zimmerman, Paul2004 Singing the blues: Years of timing anthem has me asking why some insist on dragging it out
Sports Illustrated, February 2004.