Calling my brilliant technogeek friends!

So, my best friend had two email accounts (Yahoo and Gmail) and her LJ hacked earlier today, and all of her passwords were changed. Being rather out-of-date on hacking these days, I have questions about who/what could have done this. She said that after some time, she was able to get into her Yahoo account, and she found verification emails where whomever/whatever had compromised her accounts had changed the passwords by requesting password changes. This would lead me to believe it's probably not a bot of some sort, but what do I know? I personally would rather it be a bot, because past badness-induced paranoia about creepy exes with computer know-how cracking into stuff gives me the willies, and I wouldn't put it past certain people, you know?

So, questions:

-- Given what she's said, does this sound automated (ie, bot, virus, malware) or personal (person with intent)?
-- If it is a person, how can she track down where this originated from?
-- How can she keep from this happening again?