Nutrient content of the same type of cheese can vary widely depending on the ingredients used (e.g. cow's milk based ricotta versus goat's milk based ricotta) and the specific manufacturing process used which tends to differ from country to country.

Therefore, if you consume Italian made cheeses it is very important that you get nutritional info about these cheeses from trusted Italian sources, or there's a good chance you may be misinformed. If you consume individually packaged cheese then you are probably in luck as most of these carry basic nutritional info on their packaging.

Ricotta, in particular, is often cited as a "light cheese". However, the truth is that there are types of ricotta (and in this case Italian ricotta) that are relatively light (e.g. ricotta made of cow's milk) and ricottas that are very heavy (e.g. ricotta made of goat's whole milk). Like an Italian doctor says here, there are no "light cheeses"; just more or less fat cheeses. 

Very good and seemingly accurate nutritional info (with valid references) on Italian cheeses can be found on the pages below (unfortunately, only in Italian):

http://www.my-personaltrainer.it/nutrizione/formaggio3.html
http://www.my-personaltrainer.it/nutrizione/formaggi-magri.html

According to the info above, the lightest ricotta that one can get is a ricotta made of skimmed cow's milk.