I have a few rec's of Xander/Dean from twisting the hellmouth:

Y.E.D. vs. D'Hoffryn (http://tthfanfic.org/D6zK) by serpentlady

Summary: When things between Xander and Dean get heated, YED shows up. Good thing D'Hoffryn owes Xander. . .

Christmas in Cleveland (http://tthfanfic.org/q6yk) by Riacara

Summary: Dean thinks he will be spending Christmas alone. He is wrong. This AU. I wrote this for a Secrete Santa Challenge. John is alive in this one. The pairing is Xander/Dean. A few spoliers for season one, but not much.

Province (http://www.tthfanfic.org/Series-963) by ChessM

There are six stories in this series.

This one isn't Sam and Tara, but is Dean/Tara Everything's Temporary (http://secondalto.livejournal.com/615178.html) by secondalto

Summary: A chance encounter, a moment of respite. It has a sequel is here Tears and Laughter (http://sn-crossovers.livejournal.com/1183777.html)

OMG! Thank you SO much! XD!