Recommeded email extractors?

Hi guys

I have a yahoo and hotmail account which is full of paypal notifications from customers who have bought ebooks from me on ebay. I would like to extract these emails easily and was wondering what software you guys are using for this sort of thing.

In addition, it would be great if the software enabled you to type in a particular keyword and it would search google, yahoo etc and extract emails which are related to the particular keyword.

Any recommendations?....preferably free.

Cheers