Here's one I found on AO3:

Worlds In Collision by shirozora
In 1996 Jimmy Novak disappears on his way back home from Chicago and Castiel asks a dying man permission to use his body. In 1999 Jessica Moore encounters an angel while burning a man’s remains in a Mississippi town, far from the road to Stanford. In 2005 Sam and Dean Winchester return from Jericho with their father’s journal to an apartment on fire, where Sam learns that his girlfriend is a hunter and Dean is pulled out of the flames by something that burned a handprint into his shoulder.
With nowhere to go but to John for the truth the brothers and Jessica take off, following a trail littered with coordinates, newspaper clippings, rumors, phone calls, and messages from an angel of the Lord. Standing in their way are vengeful spirits and tricksters, poltergeists and werewolves, fallen angels and premonitions, demons and family secrets.
And then there’s Azazel.
Link: http://archiveofourown.org/works/260718

A Little Twist in the Right Direction by DestielHasThePhoneBox
When Dean drops Sam off at the apartment, neither of them expect to find a lead on the thing that killed their mother. They especially weren't expecting Jess to be the one to fight off the attacking demon, or to find out that she and her hunter turned professor cousin may know more about this than either of the Winchester brothers could have dreamed.
Link: http://archiveofourown.org/works/849938