British Journal for the Philosophy of Science

Published by Oxford University Press on behalf of British Society for the Philosophy of Science. Table of contents and abstracts starting from 1996. Full text starting from 1998 (subscribers only).
http://www3.oup.co.uk/jnls/list/phisci/

Transactions of the Luventicus Academy

Journal on the fundamentals, philosophy and history of sciences. Full articles available online.
http://www.luventicus.org/Transactions

Philosophy of Science

Journal of the Philosophy of Science Association. Provides instructiosn for authors, related links, and forthcoming issue tables of contents.
http://www.indiana.edu/~philsci/

International Studies in the Philosophy of Science

Interdisciplinary scholarly journal devoted to issues in the philosophy, history, and sociology of science.
http://www.tandf.co.uk/journals/titles/02698595.asp