Sheila is compiling a list of ways people can help. Some of them are in the comments, so be sure to read them, as well as her post. Here's a link: Something. Her next post, PayPal Donations to the Red Cross, has a link that people overseas or who don't have credit cards can use to make donations. She also is compiling a list of links. It's in the top right hand column of her site.
Locally, the Red Cross is doing quickie training for people who have some time and can volunteer to go to the site and help. Contact your local Red Cross to find out if they have a similar program, if you're interested. KPIX, the local CBS station has a page of links to ways people can help.
A caveat I wish I didn't have to post, but it has to be said: Given the nature of people, there will be some who will try to take advantage of folks' generosity and will set up charities that are scams. If you've never heard of a charity, check it out before you donate. Three places to look for information before you send money: