Idaho may be a state with relatively few people, but it certainly has a lot of counties! If you are researching family in Idaho, here are some mostly free resources for you.
FamilySearch Wiki – Idaho
Chronicling America – digitized images of Idaho historical newspapers
Idaho Genealogy – Access Genealogy
Free Idaho Genealogy Search Engines on The Ancestor Hunt
Brigham Young University, Idaho – Special Collections
RAOGK – Genealogical & Historical Societies in Idaho Links to a long list. Scroll down to see them.
Idaho State University – Digital Collections
Genealogy Today – State links for Idaho
Idaho State Historical Society – Searchable indexes
Idaho Falls Historical Society – with links to several other societies