Tony Dovolani: Scientologists Followed Me ... Because of Leah Remini

Tony Dovolani says the Church of Scientology was hot on his tail during his stint with Leah Remini on "Dancing with the Stars" ... looking for any dirt they could find to discredit her ... even by association.

Dovolani was at LAX, toting around Leah's book, 'Troublemaker,' -- when our photog asked if the Church harassed him. Tony unloaded.