The Aneurysm and AVM Foundation (TAAF) is a 501(c)(3) nonprofit organization dedicated to bettering the lives, support networks, and medical care of those affected by brain aneurysm, AVM, and other vascular malformations of the brain. Tax ID (EIN): 38-3663186.
This site only deals with intracranial (found in the cranium or brain) aneurysm or AVM. However aneurysms and AVMs can develop anywhere there are arteries in the body.