http://img825.imageshack.us/img825/2668/letterfromafriend.jpg

http://img825.imageshack.us/img825/2668/letterfromafriend.jpg
http://img825.imageshack.us/img825/2668/letterfromafriend.jpg
http://img825.imageshack.us/img825/2668/letterfromafriend.jpg
http://img825.imageshack.us/img825/2668/letterfromafriend.jpg
http://img825.imageshack.us/img825/2668/letterfromafriend.jpg

http://img825.imageshack.us/img825/2668/letterfromafriend.jpg
http://img825.imageshack.us/img825/2668/letterfromafriend.jpg
http://img825.imageshack.us/img825/2668/letterfromafriend.jpg

So when you recieved this letter from a courier, where did it say you caused a bit of a stir in?

Purewater Run is most likely your location that you demonstrated the Thu'um.

Who the hell are those letters from anyway?

If you shouted somewhere, your "friend" finds out, and points you to the location of a word of power. This is much like going to the Graybeards to find words of power, but a courier comes to you, instead of you going to the Graybeards. Happens randomly.

I used my Thu'um for the first time at the location where I slayed my first dragon and that was outside of Whiterun and not Purewater Run.
And I used it again after that against some skeletons, rat but that wasn't at the Purewater Run.

In caves, ruins, cities. I think someone said that the letters come from Delphine.

If I have to guess, it is either Delphine, your personal stalker, or a drunkard.

I love it when the letters says that I've caused a stir in a dungeon somewhere where I know for a fact I didn't leave a single being alive.

They should only occur when you've shouted in a populated area, but apparently there's a very wide definition of that.

As for who sent them - I've seen people suggest Delphine, Paarthurnax, one of the Greybeards, Talos, Ma'iq the Liar, Esbern, the courier himself, an unknown Blade, the other Dragonborn from the upcoming DLC and probably a few others.

I've had that happen to me aswell, soon after I had just left a dungeon a courier gave me that letter from a someone in that dungeon. I believe one of the draugrs wanted thank me for killing him.

Yes they should restrict it to the populated settlements - the major towns and places like dragonbridge.

I've had the letter after apparently causing a bit of stir in dungeons populated only by draugr - it's kind of nice to hear zombies find the time to gossip about who's been using the thum in their tomb.

Well, most of then aren't willingly undead...

Also, Be weary of which dungeons the letters send you to. Completing the ones that have attached quests can seriously screw up your game. I tend to run from the couriers myself.

Don't know why, but Ma'iq makes the most sense to me now that i think about it. I used to be so damn sure it was Delphine. Thanks for ruining that for me LOL.