Startup admin (Santiago de Chile)

Hola!

I have just arrived in Santiago, I am very excited. I do need to do some admin to get going. Can anyone recommend a cell service provider? Are there prepaid options etc?

I am staying at Gallo con tacos hostel on Almirante Riveros in Providencia - does anyone know of shops and banks in the area? The owners of the hostel unfortunately do not know English (or if someone is available to show me around, that would be even better!)

Thank you for everyone and their help!
Ryno