You can try www.charitynavagator.org. Be very careful who you give to and always research them before giving to them :)
I have just been solicited by a charity. How can I tell if it is legitimate?
Just say no, solicitors, managers, accountants, not for profit owners are paid commissions. After everyone gets paid maybe 10% goes to the cause. Don't get me wrong, benevolence is a wonderful thing and should be part of our lives. If you feel the need to donate look to your local community ie; religious orders, boys/girls clubs, food pantry's, Salvation Army or things of this nature.