The problem with the ending of a season is that you're left with a void while they play reruns. That would be fine for most seasons, but this one was lackluster at best. So what's there to do with ourselves while we wait the long months for the season premiere?
If you can't go without your Supernatural fix and are tired of trolling gossip websites trying to gleam a few nuggets of info about the next season, then you might want to try reading some fan fiction. Fan fiction is stories written by the fans that take place in the Supernatural universe.
They are 100 percent amateur and usually placed on websites for people to read for free. These stories aren't approved by the producers of the show, but as long as people are not trying to sell them, they let them go. They are not licensed, so they can't legally be sold.
Anyone that watches Supernatural is familiar with the idea of fan fiction as it was an important part of Chuck's storyline. The stories can be about the brothers themselves or even peripheral characters. It's nice to read stories about Chuck, Crowley and other characters that aren't regularly expanded upon in the show.
The stories aren't canon, so don't be disappointed when the show deviates from what you read. The quality of the stories is dependent on the abilities of the writer. Since many are simply fans of the show with little writing ability, the quality can be hit or miss. Fan fiction is a fun and important part of any show, so look it up and check it out.