For those who do research on the signing statement, the reliable place to go for the longest time has been the "Weekly Compilation of Presidential Documents." It has reliably been tracking everything that happens in the White House (within limits) since 1965, and since 1993 it has been online and searchable. Thus if you are looking for signing statements, all you need to enter is "Statement on Signing," and it will spit out each and every signing statement for that year. That is until the Obama administration.
If you are looking to the Weekly Comp to search out Obama signing statements, don't. As of January 26--just six days after Obama was inaugurated--the Weekly Comps stopped updating online. Instead, everything has seemingly shifted to the "Daily Compilation of Presidential Documents," which you can browse by month, but searching is a different question. If you want to search, you end up searching all government publications, which is not the same as searching one publication by year. So now if you enter "Statement on Signing", you will get your signing statements, but instead you will get all signing statements in the database.
I don't want to sound paranoid, but is it coincidence that trying to track the current president's signing statements just got harder and not easier?