RK Wheeler 
The Gnomes of Nome [EPUB ebook] 
The Dwarf Wars

Gnomes and dwarves were related in ages past.  Angelica and her brother Jonah are recruited by the archangel Gabriel to find the Gnomes of Nome and retrieve the lost staff of Moses before Armageddon begins.

They must seek help from Alaska natives to find these legendary little people who live beneath the mountains.  They find themselves trapped in a war between the gnomes and the dwarves, their sworn enemies.

Angelica and Jonah discover that they have angelic blood and must develop their powers and abilities while they seek allies if they are to survive their journey to find Asgard.