The most current editions that contain most of the Corpus Hermeticum:
Salaman, Clement, Dorine van Oyen, William D. Wharton, and Jean-Pierre Mahé, eds. The Way of Hermes: The Corpus Hermeticum [and] the Definitions of Hermes Trismegistus to Asclepius. Rochester, VE: Inner Traditions, 1999. Reprint, 2000.
Copenhaver, Brian P., ed. Hermetica: The Greek Corpus Hermeticum and the Latin Asclepius in a New English Translation, with Notes and Introduction. Cambridge, New York, NY, USA: Cambridge University Press, 1995.
Older editions that may still be available in libraries, or in reprint editions:
Scott, Walter, ed. Hermetica: The Ancient Greek and Latin Writings Which Contain Religious or Philosophic Teachings Ascribed to Hermes Trismegistus. (v. 1 Text in Greek, Latin and English -- v. 2. Notes on the Corpus Hermeticum -- v. 3. Notes on the Latin Asclepius and the Hermetic excerpts of Stobaeus -- v. 4. Testimonia / with introduction, addenda and indices by A.S. Ferguson.) Boston New York: Shambhala, 1985. Reprint, Greek and Latin, with English translation. Reprint. Previously published: Boulder, CO: Hermes House, 1982; originally published: Oxford : Clarendon Press, 1924-1936.
Mead, George Robert Stow, ed. Thrice-Greatest Hermes: Studies in Hellenistic Theosophy and Gnosis, Being a Translation of the Extant Sermons and Fragments of the Trismegistic Literature, with Prolegomena, Commentaries, and Notes. Vol. v. 1. Prolegomena -- v. 2. Sermons -- v. 3. Excerpts and fragments. (3 volumes together in 1992 edition). York Beach, ME: Samuel Weiser, Inc, 1992. Reprint, Originally published: London & Benares : Theosophical Publishing Society, 1906.
Fowden, Garth. The Egyptian Hermes: A Historical Approach to the Late Pagan Mind. Princeton, NJ: Princeton University Press, 1993. Reprint, Originally published: Cambridge; New York: Cambridge University Press, 1986. With new preface.
Faivre, Antoine. The Eternal Hermes: From Greek God to Alchemical Magus. Phanes Press, 2000.
Green, Tamara. The City of the Moon God: Religious Traditions of Harran. Leiden; New York: E.J. Brill, 1992.