Spelt is an ancestor to wheat. The grain, just like wheat, does not have a husk and therefore is referred to as a "berry." The berry is smaller than normal wheat berries and as such most likely have a higher diastatic power (compare 6-row to 2-row, the germ constitutes a higher percentage of the grain). There are a few commercial examples of beers brewed with spelt, one of which is New Holland Brewing Company's Golden Cap Saison.
Brewing with spelt can be done in two ways. One is with raw spelt and conducting a cereal mash, the other is finding a supplier (or petitioning your local homebrewing supply store) that carries malted spelt. Using malted spelt will increase the diastatic power of your mash, simply mill and add to your mash as normal.