I need to find a website that lists the various forms of graphical
eagles, what their origins are, and what exactly they mean.  A common
example of an eagle I am referring to is the "Phoenix" eagle.  Another
example, which I don't know the name of (hence this question), can be
found here: http://www.omerta-eve.com/ .

I do NOT want images of real-life eagles.  I am looking specifically
for various graphical images of eagles that have been used on seals
(i.e. the US seal), or shields, or as part of icons.  The example on
that "omerta" site is a good idea of what I am looking for.

So you know, I spent a good deal of time searching for a listing of
these, and I found nothing.  Perhaps you can do better.

Thank you very much.

Hello.

The eagle has indeed been a popular symbol on seals and flags for
hundreds of years.  You should be able to find all the graphical
representations of eagles that you could possibly want at Flags of the
World at http://flagspot.net/flags/.  They have a keyword search which
allows you to search the flags and seals in their database by object. 
The many kinds of eagles are classified by keywords, beginning at
http://flagspot.net/flags/keyworde.html#ea.

Some graphical representations that I feel best represent the
archetypal eagle forms, with short explanations of their historical
origins taken from FOTW and from other research.

The German/Holy Roman Imperial Eagle - The black eagle of the Holy
Roman Empire was originally single-headed (it was first adopted by
Emperor Friedrich II), but then in 1401 a double-headed eagle (see
below) began to be used, possibly to emulated Byzantine practice. 
This eagle recurred in the flags of early modern Prussia and in
certain symbols of modern Austria and Germany.
http://flagspot.net/flags/de-pr701.html

Double-headed Eagle - "The double-headed eagle was the symbol of the
Pal[a]iologoi, the last
Greek-speaking "Roman" (i.e. Byzantine) dynasty to rule from
Constantinople. The Emperor Michael VIII Paliologos. recaptured
Constantinople from the Crusaders in 1261, from a state based in Asia
Minor; the double-headed eagle symbolized the dynasty's interests in
both Asia and Europe, and was kept despite the fact that virtually all
of the Asian possessions were gobbled up
by the Ottomans within a generation of the recapture of the City. . .
The double-headed eagle had in the two centuries of Pal[a]iologan rule
become identified not just with the dynasty but w/the Empire itself
and, more generally, with institutions and cultural ideas
outside the Byzantine Empire. . . "  Therefore, the double-headed
eagle got associated with Eastern Orthodoxy and was adopted by the
Russian tsars.
http://flagspot.net/flags/gr-ortho.html
http://flagspot.net/flags/ru_1914.html
http://flagspot.net/flags/al-1918.html 

The Aztec Eagle - From the Aztec migration story - told well at
http://flagspot.net/flags/mx).html
http://flagspot.net/images/m/mx)reve.gif
http://flagspot.net/flags/mx_emp.html

Eagle of Saladin - http://flagspot.net/flags/eg.html
A golden, metallic eagle, this graphical representation was used by
Salah ad-Din, the famous ruler of Egypt and Syria and reconquerer of
Jerusalem from the Crusaders.  It has been used in modern times by
states in Egypt and Iraq.

U.S. Bald Eagle
The U.S. Bald Eagle at the same time emulates the Roman imperial
symbol and adds a unique twist by depicting the North American eagle,
fitting for the new republic.  The presidential flag below is probably
the best-known example of this eagle.
http://flagspot.net/flags/us-pres.html

Thanks for your interesting question and thanks for using Google
Answers.  If you need any clarification, please let me know.

surajambar-ga

This was a great answer!  I was pulling my hair out thinking of where
I could find something like this, and you pulled it off in spades. 
Thanks so much!

Is this what you're after:
http://www.geocities.com/abcheraldry/birds.html