On their site you can find all kinds of valuable resources such as a list of early signs to watch for, an explanation of the seven stages of Alzheimer's, advice for caregivers and advice on living with the disease for those who have been diagnosed.
You can also find your local chapter and help in your community.
For me, my understanding of Alzheimer's disease dramatically changed after learning about what happens to the brain. See the Alzheimer's Association's Interactive Tour; Inside the Brain, for more on how the disease affects this vital organ.
The Alzheimer's Association offers a 24/7 helpline that you can reach at 1.800.272.3900.