Santarém is about 36 hours by river boat from Manaus and a couple of days from Belem, making it an ideal place for a few days' stopover on a trip along the Amazon. Boats leave Manaus every day besides Sunday. There are usually 3 boats leaving from Manaus, however on Wednesdays only one boat leaves and costs R10 more than usual for first class. Usual cost is about R110-120 for first class (top deck with a hammock.)
There's a domestic airport(Santarém-Maestro Wilson Fonseca Airport), but few foreign travelers use it to get in. It's handy if the Amazon gets to you and you need a quick ride out, though.
A few bar-come restaurants along the Beira Rio, particularly downstream from the center.
There is free wifi available at Praça da Matriz.
Santarém has two ports: Docas do Pará serves farther destination like Manaus and Belém while a smaller port near Praça Tiradentes serves destinations on the Tapajós river and other destinations like Monte Alegre, Alenquer and Macapa. You should be aware that boats advertised as departing for Macapa actually dock in Santana and from there you will need to take a bus or taxi.