Academic dictionaries & encyclopaedias are important places to start your research, especially if you are new to a topic.
They summarise existing research, and are especially useful in helping define terminology and concepts, assisting you to get a basic understanding of the subject or idea. Articles in encyclopaedias can also point you towards some of the key literature on a topic.
Do not rely on Web sources, as these are often unreliable!
A great starting point for Psychoanalysis is the PEPWeb Glossary: