As a matter of fact DUTCHEZZ just gave you the best advice of all
You should definitely use some PPC testing
December, for me at least, has always been a slow month and all my sales go down about 20%. So, I use PPC and Adwords to increase sales. Also, this way you can see what products will actually sell and what products dont. Just because you have a lot of products that does not mean people will buy. I learned the hard way. Sometimes you put in time and money and get 'zippo' for all your efforts and then sometimes you develop a winner
... so go with advertising campaigns because it will be the only way to find out.
Good call DUTCHEZZ 