I still want to know how did whats his name (not even going to bother to look it up) got off Jakko after he and Finn crash landed in the dual-seat Tie Fighter.
The Resistance knew he was there so my guess is that a rescue ship came and got him.
There isn't a full explanation for that, yet. In the movie, he just says that he woke up at night and saw no one around.
In the novelization of the movie by Alan Dean Foster, there is a little bit more, with Poe stating that he was picked by a trader as he wandering the desert.
“I wasn’t dead, just momentarily out of it,” the pilot explained. “Came around long enough to see that you had got out. Pulled out of the dive just long enough to set down—hard. Impact threw me clear. Woke up at night; no you, no ship, no nothing. Went looking—in the wrong direction. Got picked up by some itinerant trader.” He grinned. “Tell you all about it sometime.”
Edited to Add:
This is what happens when you don't read the chapters in order. There is a significant amount of space allotted to what happened to Poe after he woke up from the crash. He was found by a Blarina scavenger called Naka Iit, who promised to take him to another part of Jakku called the Blowback Town, to meet another Blarina - a merchant called Ohn Gos. After a short bit of adventure, I expect that the meeting did happen, leading to Poe finding a way off Jakku.
