Handbook of CCD Astronomy, Howell, Cambridge Press

Astronomical Photometry, Henden, A and Kaitchuck, R. Van nostrad
Reinhold Compnay, 1982 (somewhat dated on detectors but good treatment
of data analysis)

Astrophysical Techniques, 2nd Edition, Kitchen, C. IOP Publishing
Ltd 1991 (Good general overview of the physical basis for astronomical
observations)

Astronomical Observations, Walker, G., Cambridge 1987 (a solid book
with lots of nitty gritty information)

Observational Astronomy, Birney, D., Cambridge 1991

Advanced Amateur Astronomy, North, G. , 2nd ed, Cambridge 1997

Observational Astrophysics, Lena et al, Springer 1996