Bottom Line Books Board Room Classics Double Billing Des Moines, Iowa

On 10/18/10 Bottom Line Yearbook was shipped & recieved by me. When I recieved the book NO invoice/packing list was included therein. 
 On 11/15/10 I paid $15.00 thru my bank system of direct payment
 on 12/13/10 I paid $16.90 thru my bank system of direct payment.
 Siince then I have recieved several invoices stating that I owe $16.90, the last one so far on2/5/11. The book sold for $31.90.

 I sought many way to try to contact the Company(which I assumed was Large) only to run up a stone wall- Phone you get no answer-- & theres no way to find them on-line.
 I guess my next move will to go the Bank & see if they can help.
   The only thing that concerns me is how this will affect my credit rating which has an excellent rating so far.