The Instituto Brasileiro de Geografia e EstatÃstica provides extensive survey data on Brasil, including economic indicators and population. An interactive map allows for online access. Downloads are available through their file server. Data on the municipial level can be accessed here.
Finally, the company Empresa Paulista de Planejamento Metropolitano SA (Emplasa), offers cartographic material for SÃ£o Paulo. Here is a link to download extensive pdf reports with maps on its 39 municipalities.