How do we get charities involved.

Over the last few months i have mailed a lot of organisations asking if they would be interested in our services,we have offered to pay direct a commission fee to the charities,but surprisingly i have had little interest except 1 reply that was negative in response and this was from a large organisation.
So does this mean charities are not interested in the "Small" circle of fundraisers who are willing to help? i am very dubious of the reactions and wonder if my efforts are worthwhile.
I am sure we could help raise a lot of funds through the year.