I would like to collect some census data for every block group in New England. I'm primarily interested in median income and median age, and ideally I'd like a large .csv file with one row per census block group and one column per variable (e.g. id variables, median_income, etc.).
American FactFinder seems almost useless for this kind of thing.
Does the census have a "bulk data export" option?
I'd recommend using the ACS Summary File Retrieval Tool. It's a macro-enabled Excel workbook that allows for the batch downloading of ACS data for all tracts and block groups within an entire state. This makes it more powerful than the FactFinder website, but it does the downloading of the text files and linking LOGRECNOs for you. Takes less than 30 seconds per state per table. Here's a screenshot:
From http://www.census.gov/newsroom/releases/archives/2010_census/cb11-cn151.html, there's a link for the Census Bureau's FTP site. You'll have to know how to decipher the file names to get what you want, but since you're looking for bulk data, I assume you know how to do that. You'll want an FTP client for bulk download. Then you can use your unzipper to extract the data. At the end you'll need to merge all the data, but it's actually manageable. I've done it for selected block group data for 3 states.
In addition to the FTP site and the ACS summary file retrieval tool, there are two other possibilities for downloading census data for small geographies in bulk. One would be the NHGIS at Univ Minnesota, which is primarily a historical archive but also contains the latest datasets. Another option would be the Missouri Census Data Center's tools. The former is simpler and more GUI-based, while the latter is a little more challenging but provides you with a lot more customization options. I wrote a post a while back that compared all these sources, as I was attempting to do something similar:
http://gothos.info/2013/05/downloading-data-for-small-census-geographies-in-bulk/
