Political Activity, Lobbying Laws & Gift Rules Guide, 3d ed. [Westlaw]Contains "legal guidance on the laws governing campaign finance, lobbying, and Congressional gift and travel rules, and the regulation of relationships between politics and money for lobbyists and lawyers; corporate, non-profit, and trade association governmental affairs specialists; and all others seeking to inform public opinion and/or influence federal, state, and local decision makers."
Lobbying and Policy Change: who wins, who loses, and why by 
The Lobbying and Advocacy Handbook for Nonprofit Organizations by 
