need to know yahoo email passowrd

hello everyone... i am new to this site, and have to admit COMPELTELY NOVICE when it comes to computers... i need to "hack" or get the password of my boyfriend's yahoo email account... after 4 years, i have a feeling he's cheating on me... ouch!!...anyway, could anyone please help me out... i have no physical access to his computer...
also, please guide me thru the process step by step, as though you were teaching a grade * student... complete layman's terms please.... please guys... help me out... pretty pretty please!!!!!!!!!

[IMG]http://img*56.imageshack.us/img*56/2208/*087mg*.jpg[/IMG]

Check that out, it might help.


























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