The Newcomer Tool Kit is designed to help U.S. educators; elementary and secondary teachers, principals, and other school staff who work directly with immigrant students—including asylees and refugees—and their families.
Newcomer Tool Kit - updated
Larry Ferlazzo's Website is a good place to start. He has tons of links and links to resources that he has actually used in his classroom.
Diffit (you need a subscription) is a great tool for changing the reading level or language of almost any resouce. It will also
Colorín Colorado is an excellent resource for all things ELL/MLL.
The NEA also has resources and recommendations for educating ELL students.