I purchased a copy of the Clone Campaigns game only to find out that it is necessary to have the full version of Battlegrounds installed first. The "friend" that sold it to me neglected to tell me it was an expansion pack game. Does anyone know the fastest way for me to be able to start playing today? Is there any way for the expansion pack to work without the full version.

Unfortunately no, it won't work as a stand alone product. Best but would be to return/exchange it (assuming you got it at a store and not from eBay or something). There's a combo pack available with both the original game and the Clone Campaigns expansion. You should be able to get it fairly cheap nowadays.

Kryllith

Ebay is the fastest way to go. Or it might be cheaper for you to get Galactic Battlegrounds:Saga. This has both games with all the updates included. Again, try ebay it should be cheap enough

Most Walmarts carry Saga, which includes both the game and the expansion pack for less than ten bucks.