try putting the same quetion in your favorite serch engine, and you will find tons of them but its finding the one that suit you, and that as they say is the million dollor question, you a going to have to do a lot of serching to find anything, OK heres a but, for me I got over ED with DHEA and my age is 64, try looking it up and do your background on it befroe you go anywhere near it, it can have some bab side effects for the odd person, webmd has a very good page on it, it split over 5 pages and the last one is reveiws.
As far as I know, the only natural treatment that is clinically proven to work is PRELOX. You won't see immediate results, though. PRELOX is a food supplement and should be taken everyday.
Nohard mentioned DHEA, this is not an ED treatment but it may be helpful in cases of low testosterone.
Always consult your urologist before you decide to start any treatment or natural supplement.