What size are the ads in the Newspaper?

The size is measured by columns (which are 1.5 inches wide) and inches for the height.   There is a .25 gutter between columns. What we refer to as a 2x2 is 3.25 wide by 2 inches high or about the size of business card.  

What size advertisements can we use on web?

The most common advertisement size is currently 790x90, 250x250 and 250x120 pixels.