If you're in Boston (or somewhere close) and want to get your brain scanned as part of a study, look for announcements here:

http://mollylab-1.mit.edu/mailman/listinfo/bcs-subjects

You'll get a CD with your images, and you'll get paid ($30 per hour, two hours on average).

A more comprehensive tutorial for programmers: http://heather.cs.ucdavis.edu/~matloff/R/RProg.pdf

Example: http://seemywhere.com/jeremy