In your WTP player profile, click on My Rankings - then scroll to the rankings themselves.

If you've played games this season, then each venue you have a Ranking at will have a green "toggle" next to it. This means you are subscribed to receive emails from that tavern.

If you wish to unsubscribe, you can click that green toggle and it'll turn red. This means you have unsubscribed from that bar's emails. If a bar's toggle is red, you can click it to turn it green again to re-subscribe.

Also, you can use the Season drop-down menu to go back to previous seasons and do the same as listed above. :)