If you want to see a few anti-heroes done right, I'd take a look at some of the recent fantasy series. Lewis and Tolkien did incredibly well with a hero archetype, but Stephen King creates a lasting impact with the depth and realism of his characters (see Roland of Gilead). Fantasy writers these days don't pull any punches, and with good cause. The darker, more realistic fantasy that is catching on is an improvement in my opinion. Not to say it's an entirely new idea, but it seems to be becoming more and more prevalent. A few other authors that have done extremely well with their characters (and some of my favorites) that you might want to look into if you haven't already are Anne Rice, Brandon Sanderson, George R. R. Martin, Glen Cook, and Frank Herbert. All are incredible authors; if my writing is a tenth of what they do someday, then I will count myself a lucky man.
Yes Golem is a prime example of redemption, although he went back to his wicked ways in the end in Return of the King, His redemption period of fighting himself every step of the way untill the end was spectacularly done.