It's discouraging to find a -1 vote on the first question I asked here but here's the answer to my own question anyways... As of Android 4.2.2, the Soundhound data is stored in this Sqlite3 DB: /data/data/com.melodis.midomiMusicIdentifier.freemium/databases/bookmarks.db
There's no content provider for the bookmarks so of course using the DB isn't a good idea since its subject to change in any future release of the app.