I just got to riften and meet the yarl and her steward but none of them is giving me a quest to become thane.I havent bought a house here yet but dont know what to do.Any help is appreciated.
qwert

You need to start a speciffic quest dealing with skooma traders to be able to have the option.

Heres the spoilers: http://www.uesp.net/wiki/Skyrim:Helping_Hand