Yes, a novice can put on a CAI and instal a tune, very easy.
Yes, you will need a tune. Tell your dealer (that you buy the Xcal 2 from) that you have a JMS, and he may include some JMS CAI tunes in the deal (all three 87, 91, and 93 octane tunes would be nice, maybe your dealer has the tunes on hand, and will even load them on the Xcal for you. Mine did.)
Tunes can run from "included in the price of the Xcal", to $50 to $75 for "generic but based on a particular CAI" tunes, and even more if you get a custom dyno tune special for your car.
Installing the tune is really easy, just plug into the OBD II, turn the key, and push some buttons. The CAI is a few screw and bolts, and hose clamps, really easy.
Where are you located? Maybe a fellow 05 owner in the area would be willing to help. Stangnut came over and helped with mine.
Enjoy, car will respond much better with the CAI and tune.