Just a list, no ordering. Dialog Knight-Ridder's collection of more than 250 databases, the worlds biggest collection. But you have to have an account to search them. Greatful Med Medline for free. PsychArticle Search Armin Guenther's database of articles published in journals of the major scientific publishers.
All journals listed here provide tables of contents and abstracts for some issues, at least.
An exhaustive list of psychological journals may be found at MedWeb and at the WWW Virtual Library , but not all of these journals provide ToCs, abstracts or fulltext. American Journal of Psychiatry Published by the American Psychiatric Association provides tables of contents and abstracts. Journal of Marital and Family Therapy Publication of the American Association for Marriage and Family Therapy provides ToCs and abstracts. Publishers Scientific publishers provide a vast of information on the internet, but really useful stuff is, as always, hard to find. Association of American University Presses Provides a database of publications.