Raman and IR are complimentary techniques. The functional group transitions show up at virtually the same place but the selection rules are different, so weak peaks in IR can be strong in Raman. As mjc123 mentioned, with the exception of the simplest molecules, these techniques are more useful for functional group identification. Big molecules are, to use a very scientific term, floppy, and do not often vibrate as a single coordinated whole. Vibrations are coupled to some degree, of course, but to an approximation, a carbonyl stretch on one end of a big molecule vibrates independently from an amino group on the other end of a big molecule. This is true for both Raman and IR.
The best book I know for a good intro to practical vibrational (including Raman) is Physical Methods for Chemists by Russell Drago, but I'm fairly certain it's out of print. This is a good book on physical methods anway. If you're just looking for where certain peaks show up in a spectrum, MOST companies sell spectral libraries that include entire maps for common polymers. They'll even try to identify your sample based on the spectrum. This is certainly true for IR spectra and may be available on Raman instruments as well.http://www.amazon.com/Physical-Methods-Chemists-Russell-Drago/dp/0030751764
Spectrometric Identification of Organic Compounds by Silverstein and Webster has a lot of information about experimental IR transitions, and many of these will be identical (by absorption energy) for Raman.
There are also good textbooks purely on Raman spectroscopy, but whether you need one of them depends on the level of detail you plan on going into, and what your physical chemistry and spectroscopy background is.
May I ask, is there a particular reason you're using Raman instead of FTIR? The latter is sufficient in most cases for characterization and identification of organic compounds. Raman is a more specialized technique.