where to report purchased apps(in game credits) that was never received

Hello!

Can someone please help me I reported my transaction with the app face fighter buying the 24.99 gold pack that I never got it to the app developer and they said they can't refund because they don't have the billing info and that I should contact itunes or whoever there... the problem is I keep ending up a the billing section and nothing else happens it's really aggrevating this is the second time this has happened to me(the first was metal storm and I never got the refund from that as well).

Someone please give me a direct email to a CSR to whom I can report this problem....

TIA

Jonz