TAM has its own tour operator (TAM Viagens
www.tamviagens.com.br), I'm sure they would have a tour to the Amazon.
Another one you could try is Ambiental (
www.ambiental.tur.br), they have a nice 4-day package on a jungle hotel (Ariaú Amazon Towers) for R$ 2,880 which is about US$1,650 right now.