It is always useful to contact the locals in order to gather the right information about an exit, but sometimes these are not always available for you. Some also do not want to disclose their local spots at the risk of arriving a band of brainless jumpers. So remember that it will be more difficult for you to get information on urban spots. So get by !
The FBA can help you with your research. The topo as a piece of paper, torn and moist in the pocket, you already know. Today, to prepare for a jump and access all the useful information, internet is there!
The BASE beta website is certainly the most comprehensive database for exits worldwide. His research mode is fun and we participated in the development of this project.
The Paralpinisme topo is the most complete list for France. It's the digital version of what he's been doing on paper for 30 years. Fortunately it became public, thanks to the Paralpinisme association Websiite in french.
This Google map references a good number of cliffs. Fairly complete for France, it is however not very supplied internationally.
The Magland BASE Association is also offering some informations on exits in this area.
Remember that for you to benefit from public information, you too must take the time to share information on an exit that you have opened or visited.