GENERAL CLASS TEST QUESTIONS (pdf file)
TECHNICIAN CLASS TEST QUESTIONS (pdf file)
EXTRA CLASS TEST QUESTIONS (pdf file)

The first are purchase items but are maybe better
Software to purchase
Online testing to subscribe to

Theese are just online practice exams
QRZ online practice tests
EHAM online practice tests
AA9PW online practice tests
Radio Exam online practice tests
Ham Tests online

This one is a software program that runns on your computer (not online)
FREE downloadable software practice tests