Didn't know there's a site like this. Thank you for the link. Anyway, this forum would be the best source of bounty campaigns because the information you need are all in here. You just need to look through the pages for campaigns though because pages are being updated from time to time. There are many kinds of campaign like social media, signature campaigns, blog campaigns, translation and others. You just need to look for the campaign that you are interested in joining and be sure to not spam the forum.