Kicking up wine kits

I have a cuople of batches of wine with Island Mist kits. The taste was great but not enough alcohol. It was suggested that I add 1 lb of corn sugar at the start to kick it up. My questions are as follows:
1) What is the differance between corn sugar and Kero corn syrup? Where can one get corn sugar?
2) Do you measure it by weigh? We all know that liquid and dry weights are differant.

u can find it all online bro.

just type it in. the knowledge and a 3 dollar hydrometer is all u need.

gl

Wait for it to ferment down to 1.020 then bring sg back up to 1.040 then let it ferment back out. Dextrose can be found at any LHBS. You can just use regular old can sugar. Boil it down to make syrup.

Izzy those island mist kits are supposed to produce more of a wine "cooler" than an actual wine and because of this are able to be consumed as soon as you get it into a bottle. If you get a normal wine kit for something like a merlot or cab etc one good way to make it better is to add a bottle of red grape concentrate. Gives more body, better color, a bit more alcohol, and tannins etc. and acts as a nutrient for the yeast as well. As far as measuring and the difference between dextrose etc, corn syrup and dextrose are virtually the same except that dextrose is dry like white sugar and has the consistency of powdered sugar most of the time. If you use a hydrometer as bob said you can add it gradually and measure the difference in specific gravity.