Databases

CRC Handbook of Chemistry and Physics
http://www.hbcpnetbase.com/
Data may be accessed after purchasing a personal or institutional subscription.

NIST Chemistry Webbook
http://webbook.nist.gov/chemistry/
Contains databases of electronic and vibrational spectra.

Tutorials

Electronic Spectroscopy of Diatomic Molecules
http://bernath.uwaterloo.ca/media/DiatomicElectronic.pdf
Comprehensive material about electronic spectroscopy.

Electronic spectroscopy
http://rutchem.rutgers.edu/Courses_f01/Chem323b/LectG.pdf
Good section on the Franck Condon Principle.

Light Absorption and Fate of Excitation Energy
http://www.life.uiuc.edu/govindjee/biochem494/Abs.html
Another site on the Franck Condon Principle.

Photoelectron Spectroscopy
http://www.chem.qmul.ac.uk/surfaces/scc/scat5_3.htm
Information on X-ray and Ultraviolet photoelectron Spectroscopy.

Fluorescence Spectroscopy
http://phys.educ.ksu.edu/vqm/html/fluorescence.html
Interactive fluorescence spectroscopic graph (requires plugin download).