To the original poster - this too might pass (it did for us)
I have a DD who is a little older than yours (4.5 yrs). We found that when she was very little (2ish) she wanted to re-read the same dozen books over and over and over. I thought that I would go insane. I loathe repetition and am a novelty-seeker.
When she was about 2.5/3, her needs changed and she needed to be read all sorts of text from all sorts of sources (including books) in vast quantities - typical books, simple graphic novels, factual encyclopediae, newspapers, cereal boxes, signs etc. etc. etc. etc. We were also going through about 50 books a week. Luckily the library system in our city is fabulously wonderful and we exhausted the extensive selections at several branches and we are now on our third. I (and her Montessori teacher, because DD was burning through activities as school also) pondered the questions surrounding novelty-seeking that Roar and Miranda raised and wondered if I/we was doing the right thing by providing her with so much variety.
However, in the last few weeks DD's desperate need for variety (in books, and other material) seems to have passed somewhat. Now, she wants me to re-read books that she enjoyed or had more thought-provoking content. She has asked that we borrow more chapter books. She asks me to re-read 75% of a book and then stops me and proposes an alternative ending etc. The return to some repetition I think is part of the process of learning to read and she is building her sight vocabulary (so I have gone back to reading more slowly and pointing out the words again). I think that she is also using the material in books as the start of her own creative thought process, while in the past the content of a book was an end in itself.
So firstly, I think that for some children, this is a need for variety and not necessarily novelty for novelty sake. Secondly, I don't know if this need for new material is a phase for your DD, but it might be....and then this too will pass.
(I would also say though that writing on a book is the closest thing to a capital crime in our house as we have a lot of expensive/irreplaceable academic texts in the house. DD wrote on walls a couple of times when she was about 2.5, but she only wrote on a book once! I went bonkers and the consequences were so severe that she didn't try it again. For a while it was a choice between crayons OR books at any specific time. DD learns her values from me - If I treated books as disposable so would she - for me books are special and so she was required to learn to treat her books as special too. I hope that my values about sex, drugs and rock and roll are as easily transmitted when she hits her teens

, but respect for books is a good start.)
Anyway - hang in there and do what works for you. I am sorry that your public library system is so lame as we could not have got through this phase without it...
Follow Mothering