Vast stores of data are collected by the states and federal government and easily available online. Along with Census data, check out other federal and state agencies for school performance, property values, business sales by neighborhood, crime statistics, health and epidemiological data. The Durham Compass provides a great example of how to incorporate these numerous data sets and cites sources.
Connect with your regional council or planning agency. They often maintain a library of community data and can provide the GIS services needed to aggregate and understand the data.
An organization called Community Commons maintains an ever-growing set of community-level data sets and mapping tools. Check it out below: