There are five types of loons in North America and the Common Loons are the most numerous and widespread amongst their species. The Pacific Loon and the Arctic Loon are very similar looking birds with the Arctic Loon being the larger of the two. The Yellow-billed Loon is the largest member of the loon family and inhabits the central Arctic to the tip of Alaska. The Red-throated Loon can be found in the northern areas of North America and is the smallest of the group.
Avibase - the world bird database This site provides the user with a complete list of bird species, broken down per country, or in the example of the US or Canada, per state and province. Here, bird species names are available in other languages, a great asset to be used as a translation of foreign bird names.
ABA - American Birding Association This site represents an organization that maintains official records of all birds species that have been proven to have been seen inside the perimeters of the North American Continent and the surrounding bodies of water. Regular revised versions are posted to keep the bird list current at all times. This is the list used by all serious birders over their lifetime. You may be aware of the movie called the "Big Year". It was with this list that all the competing birders used in an attempt to set a new record as to how many bird species that could be seen by an individual birder in one calendar year.
I hope you will take advantage of these suggested websites. I have used each of them, in one way or another, throughout the years in my quest to better identify and understand our fine feathered friends.