Like all seasons, regular hidden immunity idols will be found by mailing me the correct CBS Survivor player. You can guess once a day, and it resets at midnight EST.
Both additional idols are found on the oldest blog of a random user on tengaged.
Freeze idol: This idol can be used whenever you want, not just during tribal. It will cause the player of your choice (can be yourself) to become frozen in ice, preventing them from voting for that round. They also will be immune from the vote, and cannot participate in the immunity challenge if it is used before the challenge.
Polar idol: This idol can also be used whenever you want. This idol contains a strong magnet that will take away and nullify an immunity necklace, hidden immunity idol, or freeze idol. It can only be used on a hidden immunity idol or freeze idol after they are played to prevent that play from happening. If you are nullifying a freeze idol, it must be used before 1 hour passes after the play, or before the votes are read.
If you have any questions, just ask! This is intended to prevent any confusion surrounding the idols.