my children have love Dr. Suess books since they were little babies! rhyming books are supposed to be especially good for building a child's language skills. my kids also love all the board books such as "first words", "first numbers", "first dictionary", etc. (the kind where they just have pictures and a word labeling each picture). just remember, even if your baby wants to just look at the pictures, not listen to the story, you can still point things out such as colors, animals, shapes, etc. and she will soak up all that information! and try not to get impatient if she wants to read the same book 10x in a row, repetition is an important part of language development.
used book stores usually carry like-new copies of books such as Dr. Suess for about half the cost of buying them new. if you don't like the idea of previously-owned books, try a store like Ross that sells new items for a discounted price
happy reading!
PS i forgot...the Little Critter books are another one of my girls' favorite series! and they have cute stories and good morals