The Saguaro Astronomy Club database has surface brightness data on a number of deep-sky objects and can be downloaded at http://www.saguaroastro.org/content/downloads.htm
Here's a list of the Messier galaxies, their integrated visual magnitudes, and their surface brightnesses:
M31 3.4 13.6
M32 8.1 12.7
M33 5.7 14.2
M51 8.4 12.6
M58 9.7 13.0
M59 9.6 12.5
M60 8.8 12.8
M61 9.7 13.4
M63 8.6 13.6
M64 8.5 12.4
M65 9.3 12.4
M66 8.9 12.5
M74 9.4 14.4
M77 8.9 13.2
M81 6.9 13.0
M82 8.4 12.8
M83 7.6 13.2
M84 9.1 12.3
M85 9.1 13.0
M86 8.9 13.9
M87 8.6 12.7
M88 9.6 12.6
M89 9.8 12.3
M90 9.5 13.6
M91 10.2 13.3
M94 8.2 13.5
M95 9.7 13.5
M96 9.2 12.9
M98 10.1 13.2
M99 9.9 13.0
M100 9.3 13.0
M101 7.9 14.8
M104 8.0 11.6
M105 9.3 12.1
M106 8.4 13.8
M108 10.0 13.0
M109 9.8 13.5
I also have data on a number of showcase NGC galaxies:
NGC 253 7.6 13.2
NGC 253 7.6 13.2
NGC 891 9.9 13.7
NGC 1097 9.2 13.6
NGC 2841 9.2 12.4
NGC 2903 9.0 13.4
NGC 2997 9.3 13.6
NGC 3115 8.9 12.1
NGC 3628 9.5 13.7
NGC 4449 9.6 12.8
NGC 4565 9.6 12.9
NGC 5005 10.8 12.7
NGC 5746 10.3 12.3
NGC 5907 10.3 13.4
NGC 6946 8.8 14.2
NGC 7331 9.5 13.3
NGC 7479 10.8 13.4
Dave Mitsky