I'll be honest, I left most of the 'liberty movement' awhile ago, because I got tired of their constant bickering about who was being mean to who on twitter, but I do know that Larken Rose's "The Most Dangerous Superstition" is a good book, I had already accepted the ideas and concepts laid out in the book, but it summed them up quite well, and in a fairly non-offensive manner.

One that is a very old, but very good one is Spooner's famous No Treason: The Constitution of No Authority, which will hit on the fact the constitution, particularly the 2nd amendment, is ignored until it is politically helpful to invoke it.

I'd personally make it a point to target gun owners who see the ridiculousness going on, and want to distance themselves from it, they're being disenfranchised by the trumpians who are going out making fools of themselves, and have NO friends in the mainstream left.