As far as I know there are still no ‘offical’ English translations available of the – highly interesting – work of Gilbert Simondon. However, there do circulate some translations on the internet – most notably his book On the Modes of Existence of Technical Objects. Others include ‘The Position of the Problem of Ontogenesis’, ‘Technical Mentality’ and a 1966 review by Gilles Deleuze – for whom Simondon was a great inspiration (think of his distinction between singularities and individuals and the notion of individuation) – of ‘L’Individu et sa genese physico-biologique’. All of these are truly worthwile.
Some translations of the work of Simondon I didn’t know of (thanks to Terrence Blake from Agent Swarm)
Topology, Chronology and Order of Magnitude of Physical Individuation
Topology and Ontogenesis
The Physico-Biological Genesis of the Individual
The Individual and Its Physico-Biological Genesis
Chapter 1 of Physic and Collective Individuation
A new translation of Gilbert Simondon’s ‘Two Lessons on Animal and Man’ by Drew Burk will be published by Univocal Publishing. I haven’t heard of the publisher, but it seems promising; check out their website here. (Thanks to Drew Burk for bringing it to my attention)