The best place to go for my group's software that is open source is github: WING.NUS @ GitHub.

For all other research output, including tools and corpora, see the download page of WING. Occasional, for fee software can also be found in the NUS Research2Market portal.

Most of what I've done professionally for natural language processing during my Ph.D. years is available from the Columbia NLP group's home page. This includes the verber, centrifuser and segmenter packages.

Besides that: