This Gist contains a script and supporting files for building a OneBusAway GTFS bundle with data for all agencies in the Baltimore/Washington area that have publicly released their data.
Configuration parameters come from two sheets in a Google Docs document:
https://docs.google.com/spreadsheet/ccc?key=0AvrkbWHnoksNdGdYam4wX214SXpoRmdia0FEalZvUHc&usp=sharing
The dependency on Google Docs could easily be removed by removing that part of download.sh
and using a locally-maintained CSV file instead.