When there were several homeless people who died from the heat in Phoenix, I did a search to see how I could help other homeless in the area. I came across the website for Shoebox Ministry!
This is a great organization. You fill a shoebox with basic sundries and drop it off to the Shoebox ministry folks. (It's actually a drop off at someone's house) They then distribute it to people who really appreciate the contribution.
If you are looking for something to do to make a difference, check them out. They will also give you a receipt if you want one for a tax deduction.