The Young Adult Library Services Association (a branch of the American Library Association) is an excellent resource for finding quality YAL. The site provides lists of award winning books for various age groups. Printz Award winners and runner-ups tend to be excellent texts.
The National Book Award is arguably the top honor for books by American authors. The awards have an entire category for Young People's Literature (with a yearly winner, runner up, and longlist of titles considered for the award).
The New York Times YAL Bestseller list is an excellent way to determine what texts--fiction and nonfiction--that adolescents, teachers, and parents are buying.
Project Lit Community is a teacher-centered group that focuses on the books that our 6-12th grade students will like to read. It grew out of a high school ELA class project and has grown since.
The Horn Book Magazine has a long history of providing reviews of excellent books for children and adolescents. This resource differentiates book reviews for early childhood, early elementary, primary, middle school, and high school (with some subcategories therein). Some of their materials are free while others require a subscription (contact me for specific information).

Click on Images below for links to compilations of quality Young Adult Literature