African-American Teen Fiction with summaries
http://www.blackbooksdirect.com/teenfiction.html

Teens Read Too! – blog with amazing book covers, summaries, contests, and reading lists
http://teensreadtoo.com/

Teen Urban Fiction – Urban fiction for teens from the Grand Rapids Public Library wiki
http://www.grpl.org/wiki/index.php/Urban_Fiction_for_Teens

Young Adult Books in Series and Sequels
http://www.bettendorflibrary.com/bpl-bin/series.pl

TeenReads.com Cool New Books Round-up
http://www.teenreads.com/features/cool-new-books.asp

Best Books for Young Adults by YALSA
http://www.ala.org/ala/mgrps/divs/yalsa/booklistsawards/bestbooksya/bbyahome.cfm

Great Graphic Novels for Teens by YALSA
http://www.ala.org/ala/mgrps/divs/yalsa/booklistsawards/greatgraphicnovelsforteens/gn.cfm

Teens Top Ten – "teen choice" list, where teens nominate and choose their favorite books of the previous year – from the YALSA website
http://www.ala.org/ala/mgrps/divs/yalsa/teenreading/teenstopten/teenstopten.cfm

Teen/Young Adult Fiction Index – Booklists by Theme
http://librarybooklists.org/fiction/ya/yaindex.htm

Guys Lit Wire - Great Books for Guys!
http://guyslitwire.blogspot.com/

50 Best Blogs for Teen Readers
http://www.onlinedegrees.net/blog/2010/50-best-blogs-for-teen-readers/

LibraryThing, TAG: Young Adult Literature
http://www.librarything.com/tag/young+adult+literature

TeensReads.com Ultimate Reading List
http://teenreads.com/features/ultimate-reading-list.asp

Reading Rants! - a fantastic collection of out of the ordinary book lists
http://www.readingrants.org/

Michigan eLibrary Teen Database Portal - providing reliable resources on all subjects, they're great for homework help or general information seeking. There's even links for Homework Help, College Prep, and Life Skills.
http://mel.org/index.php?P=SPT--BrowseResourcesTeens&ParentId=844