If you follow this guide, you will end up with the following:
Your contacts transferred
Your calendar transferred
Your email archive transferred, complete with folders
Let's start with contacts. Transferring your contacts from Yahoo to Gmail is a pretty trivial task. All you need to do is to export the contacts and then import them in your Gmail-account. This is how:
Moving your calendar from Yahoo Calendar is almost as easy as moving your contacts. It's the same workflow: export from Yahoo Calendar and import into Google Calendar. This is how:
Last, but definitely not least, we need to transfer the email archive. For this we will use YippieMove. There are some alternative solutions for getting your emails across such as TrueSwitch (see the comparison here), but it won't transfer folders or read/unread status. Below is a video on how to use YippieMove. The only difference here is that we will use select "Yahoo" in Step 1 and "Gmail" in Step 2.
Jump to YippieMove. Pretty easy, huh? If you have any questions about the contact or calendar migration, please post them below. If you have any questions about YippieMove, please contact the support.