Ham Cram - Free technician-class license cram course. Six hour power point presentation covering every question in the FCC question pool. Easy instructions. [Requires MS Power Point] - http://w9pe.us/
RadioExam.org - online practice for US FCC Amateur Radio exams - http://www.radioexam.org/
Practice Exams - View flash cards for all current question pools, or take practice tests. The site keeps statistics on your answers to help gauge your progress. [Free registration required] - http://www.kb0mga.net/exams/
Sunnyvale VEC ARC - one of US FCC-recognized Volunteer Examiner Coordinator organizations able to give Amateur Radio exams (California, Nevada, Oregon) - http://www.amateur-radio.org/
W5YI VEC - one of US FCC-recognized Volunteer Examiner Coordinator organizations able to give Amateur Radio exams (nationwide) - http://www.w5yi.org/
ARRL/VEC - one of US FCC-recognized Volunteer Examiner Coordinator organizations able to give Amateur Radio exams (nationwide) - http://www.arrl.org/arrlvec/
US FCC Exams - Europe - Information on US FCC Examinations for Europe. - http://www.qsl.net/dl4vcw/vec.htm
Hamstudy.com - Self-study courses for Canadian Basic and Advanced amateur radio exams. - http://www.hamstudy.com/