In this screencast, I show how to use Mendeley reference manager to automatically generate bib files into a centralized folder where latex can find so you don’t have to manage them manually.
Basically if you but your .bib files into the following folder:
~/texmf/bibtex/bib (UNIX)
C:Usersusernametexmpbibtexbib (windows)
TeXLive’s latex will be able to find them without you specifying path for them. I find this very convenient, since you can have a centralized folder for .bib files and you don’t have to copy .bib file to the latex source folder whenever you update your reference library.