Oh, I've always wanted to participate in a discussion like this... Are INFJs rare in fiction, too? I only read teen/children's fiction (I'm very sheltered and all else is deemed inappropriate...) and some classics, but they're very hard to find in those... Which isn't always enlightening, as I have this selfish need to either love or relate to a character in order to truly enjoy a book.
There is one character who I really relate to, Vin from Mistborn... I don't believe many have read Mistborn, but it's truly a good book series, with a very unique plot and an intriguing world and unbelievably wonderful characters; I highly suggest reading it. I really related to Vin, the main character, when reading it, which is quite odd because she doesn't seem like an INFJ at all at first glance. She's a fighter, and cares little for moral cause so much as she wants to protect those she loves and keep herself alive, but this I attribute to her hard life as a child... She is very introverted, Ni, as she does see connections others don't and thinks ahead, and has a very well developed Se that helps her perform wise actions from her rough upbringing. Behind that, she has Fe, which clashes with the other main character's strong Fi. She has a subtle but present compassion for everyone, and begs (internally) for mercy where her Fi counterpart desires revenge and murder of enemies. She doesn't speak often, but when she does, it's very logical, as characteristic of Tis.
She could also be ISTP, yet she seems more inclined to INFJ tendencies than one with natural ISTP ways...
I also relate a bit to Peeta and Delly from the Hunger Games (I really need to read some non-mainstream books...), though I think Delly is probably ENFJ. (Peeta could be INFJ... I'm not sure exactly yet.)
Oh! And Risa from Unwind seems VERY INFJ.