I've read all the Outlander books. Twice. It's a ripping good yarn, but I daresay she's a tad "off" on some of her history.

As of right now, my favourite series of books (which are not really an interconnected series, but rather represent the chronological list of works by the author) is the Waverley novels by Sir Walter Scott. As well as the Tales of my Landlord books. Heck, everything he wrote is fabulous. And yes, he takes some liberty with history, though he does himself credit by explaining himself in doing so.

I've really fallen in love with his style of storytelling, and especially with the eloquent and quaint language in which he wrote. Even when he steps away from distinctly Scottish themes (such as Ivanhoe), his books are too good for me to put down.