If you are looking for something to read in Spanish, Amazon has some great titles available for relatively cheap.
The most important thing to remember when selecting a Spanish text is that you should be able to understand a high percentage of it without having to stop and look up a bunch of words. If you can understand at least 80 percent of it fluently, you have an okay selection. Ideally you'll find a book you can read at 95 percent comprehension and above.
Check out these recommended Spanish Children's books: