From Batista to Young the Mets over the last 2 years have signed around 40 free agents with most being signed to minor league contracts. 10 signings have been to pro contracts if you include the Cedeno & Hairston signings which have yet to be official.
If you look at what the 10 Pro contracts the Mets committed to in guaranteed money only it breaks down to $25.8M. $8.1M in 2011 and $17.7M in 2012.
In 2011 some of those minor league contract signings made the MLB Team as well as those signed to pro contracts. Here is a look at how the signings that played for the MLB Mets fared in 2011.
Finally here is a list of those free agent signings over the past 2 years.