The only "lies" I have come across are those pertaining to hidden subliminal images, and to be fair even those aren't real lies because for one there actually were a few "easter egg" type images in older literature and secondly the other dubious claims of subliminal images are not deliberate attempts to mislead but just paranoid, super-cynical ex-JWs succumbing to pareidolia.
Who I do see lying on youtube videos and in the postings on various internet fora, are JW elders and publishers, when they're asked questions that could expose certain unsavory aspects of their religion. Yahoo Answers' Religion and Spirituality section has many examples of JWs giving dishonest answers and comments to hide and deny unsavory facts about their religion pertaining to things like shunning and discouraging higher education.