yes you do already have that, it comes with your POD. you need to register your POD to your account (you can do this by going to www.line6.com, then log in and click the my account link a tthe top then the register gear link on the left). if it's already registered, contact the old owner to go to the same place on this site and click the remove link next to where his POD is registered in his account. then you can register it. then in line67 monkey on the *** ons tab pod farm should already have a green tick once it's registered to you.
then just install pod farm, and open the plug in within your recording software. remember that the plugin and standalone versions of pod farm are not the same. the standalone version wont work with your POD as it isn't needed. to edit your pod on your PC use the gearbox editor.
all software can be downloaded through monkey or from the downloads link at the top of this page.