Percy Jackson is still a fairly new series, so it is not yet available in the public domain. This means that it cannot be read for free online legally. The publisher has released the e-book in Kindle edition only. The audio book can may be purchased as a download directly from Random House.
If you still don't believe me, go to that site and see. Besides, why would you want to read it online?? Especially when there are so many copies available in bookstores or libraries?? Don't you see that "it cannot be read for free online legally"?? What's the matter--do you want to support cyberpirates who'd steal an honest author's book??
Wait a minute--the CARLMAN, who brings balance to The Force, should be able to bring balance to his own emotions. I don't want to be harsh with you all. Maybe some of you are used to getting everything online and expect to find the book there. Or maybe you heard somewhere that you could read it in cyberspace. Well, it simply can't be done. There. Now you know.
Whew!! I feel better. Now that I have answered that question, I shall swat it away like the pesky fly it is and be free to concentrate on my truly important mission--finding more good books!!
BTW, a Kindle is an electronic device that lets you read books. Check out the website. And check out the price before you ask your parents for one!!