The RIPS Law Librarian Blog (http://rips-sis.blogspot.com/) brought this to my attention:
The Legal Information Institute at Cornell University Law School has developed a tool to help with legal research: The Legal Citation Finder Bookmarklet (or LII Citer), available at http://topics.law.cornell.edu/lii/citer.
Once the LII Citer is saved as a bookmark, when you come across a citation on a webpage that is not hyperlinked to the text of the document, you can highlight the text and then click on the LII Citer in your bookmarks list. It should take you to the text you're looking for.
At this time, not all citations are supported, and those that are supported are limited to federal materials. The LII webpage provides additional information, and even provides sample citations for you to test it out on. I'll bet an app for you phone won't be far off!