InSite recently wrote about the Lobbying Database from opensecrets.org. The Lobbying Database tracks campaign contributions made to elected officials by lobbyists. From Insite:
The Lobbying Database is one prong of the "Who Gives" menu from opensecrets.org. The website is a product of the Center for Responsive Politics, a not-for-profit non-partisan organization that "tracks money in politics, and its effect on elections and public policy." The Lobbying Database, funded by a grant from the Sunlight Foundation, tracks spending by lobbyists since 1998 in their attempts to influence Congress and federal agencies. The database can be searched by name, industry, issue, bill number, federal agency, or foreign entity. Data is compiled from required semi-annual public disclosure statements filed by lobbyists, and presented in easy to read charts and graphs. This site provides a simple and effective tool for researchers interested in lobbying in the United States.