About spatial smoothing: http://lbc.nimh.nih.gov/fidap/spatialsmooth.html
Tutorial on Smoothing: http://www.mrc-cbu.cam.ac.uk/Imaging/smoothing.html
Thresholding with Random Field Theory: http://www.mrc-cbu.cam.ac.uk/Imaging/randomfields.html
Full contents of listings in MRC-CBU: http://www.mrc-cbu.cam.ac.uk/Imaging/contents.html
Education/MRI Tutorials: http://www.spectroscopynow.com/Spy/basehtml/SpyH/1,,9-4-17950-0-17950-directories--0,00.html
Functional MRI - Methods and Applications: http://www.fmrib.ox.ac.uk/~stuart/thesis/
Magnetic Resonance Sites on the Web: http://www.ismrm.org/mr_sites.htm#Education
MRI Tutor: http://www.mritutor.org/mritutor/
Introduction to the Principles of MRI: http://www.simplyphysics.com/IntroToMRI.html
Mathworld: http://www.mathworld.com