The first one is called Stupid and Contagious (by Caprice Crane). Its so incredibly hilarious and a fun, easy book to read if you just want some entertainment. Essentially its told from two points of view, Heaven and Brady, and just goes through their interactions as neighbors and other funny things that happen in their lives.
The second one is called Forget About It (which is also by Caprice Crane). I have only gotten about 2/3 of the way through it but yet again, Miss Crane has done it again. Hilarious. If you want something that makes you laugh a ton, its definitely the way to go. The main character, Jordan Landeau, is a push-over that has a very depressing life. She then gets hit by a car while riding her bike to work and from then on pretends to have amnesia. She gets to start over her life as the new Jordan.
The last one is an oldie but a goodie, if you will. Its called the Perks of Being a Wallflower (by Stephen Chbosky). I would have to describe it as a coming-of-age tale from the point-of-view of a 15 year old boy named Charlie. He writes these letters to an anonymous person throughout the book. Its adorable, funny, sad, all of the above. I read this about 5 years ago and I just started reading it again because I love it that much.