It is very easy for someone to send you an email that appears to be from a company like Yahoo or Paypal (to name a couple common targets).
These emails usually have links "for your convenience" to go and log onto your account. You might have used one that took you to a fraudelent site that was built to resemble Yahoo's mail signon page. By entering your ID/PW at the site, it was easily obtained. Whenever you sign onto any account online, always make sure the URL in the address bar of your browser is the right one. Also use SSL (secure signon) whenever possible and change your password at least every 3 months depending on how often you use it.
~cdogg
[tab]"All paid jobs absorb and degrade the mind"
[tab][tab]- Aristotle