I see people keep asking where the end portal is, or if someone can teleport them to the end, so I spent quite a while (thanks to Lautlos76 for helping) finding it.

The coordinates of the portal are:

x= 300

y= 38

z= 743

When looking for it, it is in an extreme hills biome, and niels has built a tent on top of where it is, if you follow the water nearby, it flows down into a cave, the portal room is down there.

Have fun, now stop asking about it :P