The American Constitution Society is making an Index of Presidential Signing Statements, 2001-2007, available online. The Index is described on the website:
A comprehensive index of presidential signing statements issued between 2001 and 2007. The index, compiled by Neil Kinkopg, associate professor of law at Georgia State University College of Law and former special assistant in the Office of Legal Counsel at the Department of Justice, provides a comprehensive list of every provision of a law objected to by the White House in a signing statement, the reason for the objection, and a link to the relevant signing statement.From BoleyBlogs and the Law Librarian Blog.