"Atheism is usually defined incorrectly as a belief system. Atheism is not a disbelief in gods or a denial of gods; it is a lack of belief in gods. Older dictionaries define atheism as "a belief that there is no God." Some dictionaries even go so far as to define Atheism as "wickedness," "sinfulness," and other derogatory adjectives. Clearly, theistic influence taints dictionaries. People cannot trust these dictionaries to define atheism. The fact that dictionaries define Atheism as "there is no God" betrays the (mono)theistic influence...
https://atheists.org/activism/resources/what-is-atheism
"The more common understanding of atheism among atheists is "not believing in any gods." No claims or denials are made - an atheist is any person who is not a theist. Sometimes this broader understanding is called
"weak" or "implicit" atheism. There is also a narrower sort of atheism, sometimes called "strong" or "explicit" atheism. Here, the atheist explicitly denies the existence of any gods - making a strong claim which will deserve support at some point.
What is Atheism..."
http://atheism.about.com/od/aboutatheism/p/atheism101.htm
Atheism (weak atheism) is an absence of belief in gods. Strong atheism is the belief that gods don't exist. Learn the difference.
If you wish to define yourself as one who has no evidence for a god or gods then you would be an agnostic;
Agnostic
1 : a person who holds the view that any ultimate reality (as God) is unknown and probably
unknowable;
broadly : one who is not committed to believing in either the existence or the
nonexistence of God or a god
http://www.merriam-webster.com/dictionary/agnostic
This is the defined category for those who have no belief either for or against god or gods. If you wish to claim atheism then you are claiming something other than the claims of agnosticism which is neither for or against theism.
You can quote all the atheist sites you want but they exist because of the implications being brought against the positive assertion that they historically made that there is no gods and they are trying to redefine their image to one that appears for all intensive purposes to be agnostic. Save yourself the time of fighting for a redefinition when it is just as simple to say I'm agnostic... it a clear and concisely defined word that from its inception has placed the people who define themselves by it as those who hold no beliefs either way concerning theism.
ATHEISM
Early modern Christian writers often failed to distinguish between non-belief in "the true
God" and non-belief in a supreme being per se, and atheism usually meant the assertion of the non-existence of the Judeo-Christian God. Strictly speaking, however, atheism is the denial of the existence of a divinity. As such, it is different from agnosticism (a suspension of belief on the question of God's existence) or simple theological heterodoxy....
....Italy enjoyed perhaps the greatest reputation in the seventeenth century as a congenial home for atheism. This perception was fostered by the presence of thinkers like Vanini, an open and avowed atheist who denied the possibility of an immaterial God creating a material world and communicating with embodied beings. Religion, Vanini insisted, was a fiction, and the only true worship was that of nature. He was burned at the stake for his "blasphemous" beliefs....
....In early-eighteenth-century
France there was a good deal of "atheism" in the many clandestine manuscripts that circulated in society and especially in the unregulated discussions that took place in the salons and cafés of Paris. Here could be found diverse libertines, radicals, and freethinkers expressing doubts about Christian dogma (including the divinity of Christ) and mocking religious beliefs in general. Many of them (including the declared atheist Nicolas Fréret) were influenced by the writings of Henri de Boulainvilliers (1658–1722), a nobleman who, by the end of his life, was a devout Spinozist. In his
Essai de métaphysique (c. 1700; Essay on metaphysics), which circulated in manuscript form, Boulainvilliers insisted that the divine creation of the world was impossible, and that nature was governed not by providence but by necessary laws. Above all, he rejected the notion of a transcendent, personal God endowed with the usual moral and psychological characteristics....
http://www.encyclopedia.com/topic/atheism.aspx