You will not need those protocol upgrades to monitor any of the public safety entities in the Baltimore area - Baltimore County, Baltimore City, and Anne Arundel County all use some flavor of Motorola P25 technology, and the SDS series of radios are capable of receiving P25 out of the box.
If you still want to purchase those protocols, you buy them directly from Uniden. They are already installed in the radio; Uniden sells you a licensing key to unlock the capability. Basically you register the radio with Uniden, verify the unit's ESN on the site - then you have the option to buy the protocols if you need them (which you do not.)
myUniden - Customer Product Registration and Support Area