Need to FAX letters TODAY to 4 PDLs....to cancel my auth.

Is there a sample letter CANCELING ACH Debit Authorizations from being taken from my acct. ANYWHERE on your site? I live in CA. PDL(ALL are internet loans)details are: 1) OneClickCash 7/10/07 borrowed $300 - paid $715 to date only $100 was for principle-still OWE $275!? 2) UnitedCashLoans 11/15/07 borrowed $250 - Have been debited $75 2X and $30 1X on same day 12/4/07? 3) LoanShop/Cimarron 11/28/07 borrowed $200-paid $120 for 1st extension 2nd due 2/4
4)CashCentral(DFS Loans) 12/13/07 borrowed $255 --this got the attempted ACH but returned 6x at least(*$30NSFx6)! Now getting letters. I need to know HOW to word the revocation of my authorization for these PDLs to debit my accts!! Please HELP!!!