The website for the U Ba Khin style of Vipassana meditation, as taught by S.N Goenka is…
On this website one can enrol for 1-day, 3-day and 10-day courses. Note that 1-day and 3-day courses can only be attended by meditators who have done at least one 10-day course.
The website for Vipassana Fellowship, an online support group that conducts online courses in Vipassana meditation is…
Here’s a very nice site with many useful resources…
And here’s one of the most authoritative sites for Theravada readings:
Guru Soul 