Minor Leaguer already created a signing table in the Library, but there's no ability to comment there, and in my opinion the discussion and link dumps are 90% of the fun and information value. As usual, post any links to information on signings/signability and I'll do my best to add it to the table and keep it promptly updated.

Past Years: 2010, 2011, 2012, 2013

Update 6/13: Per suggestions, I've added a rankings column, which is the draftee's average pre-draft rank of four sources: Baseball America (top 500), Perfect Game (top 500), scout.com (Kiley McDaniel, top 291), and MLB.com (Jon Mayo and Jim Callis, top 200). It also shows how many of those 4 lists the draftee was on, since the average will be biased upwards by non-inclusion on a list vs. being ranked too low for inclusion. I did not include Keith Law's rankings from ESPN since they are behind a paywall, and he only goes to 100. I've also added a column to record the draftee's initial minor assignment, as they occur.

Final Update 7/19: None of the 13 unsigned draftees signed at the 7/18 deadline, so total spending comes $71,400 under slot with $92,94,700 in reported spending. The table has been updated accordingly, with all signability links preserved even if they contradict the final outcomes (ie, Todd Isaacs). Minor league assignments are current as of this date but will not be updated further. Thanks to all who provided links to info.