Ancient Philosophy Resources:

History of Philosophy without any gaps: free podcast by Peter Adamson

Endoxa - An Ancient Greek and Roman Philosophy Blog by Caleb Cohoe
(includes list of journals publishing Ancient philosophy along with review times and acceptance rate AND calendar of events in Ancient philosophy)

Ancient Philosophy Societies:

Society for Ancient Greek Philosophy
Ancient Philosophy Society
International Plato Society
Plato Society of Zagreb
International Society for Neoplatonic Studies
The Canadian Aristotle Society

General Ancient Philosophy journals:

Ancient Philosophy
Ancient Philosophy Today
Apeiron
Bochumer Philosophisches Jahrbuch
       für Antike u. Mittelalter
Dionysius
Elenchos
Hermathena
Journal of Ancient Philosophy
Methexis
Philosophie Antique
Phronesis
Revue de Philosophie Ancienne
Rhizomata
Oxford Studies in Ancient Philosophy

Specialized journals for Ancient Philosophy:

Early Medicine and Science
The International Journal of the Platonic
                                                        Tradition
Polis
Plato

Other history of philosophy journals that regularly publish Ancient philosophy include:

Archiv für Geschichte der Philosophie
British Journal for the History of Philosophy
History of Philosophy Quaterly
Journal of the History of Philosophy

General philosophical journals that publish Ancient philosophy include:

Philosopher's Imprint
Philosophical Review
Philosophy and Phenomenological Research

Classics journals that publish Ancient philosophy include:

Classical Philology
The Classical Quarterly
Mnemosyne
Rheinisches Museum fuer Philologie
The Journal of Hellenic Studies

Specialized Ancient Philosophy graduate programs:*

Cambridge University
Cornell University
Humboldt University, Berlin
KU Leuven 
Munich School of Ancient Philosophy
New York University
Northwestern University
Oxford University
Princeton University
Stanford University
Yale University
UC Berkeley
University of Chicago
University of Michigan, Ann Arbor
University of Oslo (Master)
Univeristé Paris-Sorbonne
University of Pittsburgh
University of Texas, Austin
University of Toronto

* There are, of course, quite a few other graduate programs in which students can seriously pursue Ancient philosophy. The list above contains only graduate programs that have specialized tracks (often interdepartmental and with separate requirements) for Ancient philosophy.