The Rift and The Reach

I think the Jarl offered you the possibility to buy some house. You must talk to its associate to get one.

Tonilia becomes a fence after the quest Taking Care of Business. She can be found in The Ragged Flagon in Riften.

Mallus Maccius becomes a fence after the quest Dampened Spirits is completed. He can be found in the Honningbrew Meadery near Whiterun.

Gulum-Ei becomes a fence after the quest Scoundrel's Folly. He can be found in The Winking Skeever in Solitude.

Enthir becomes a fence after the quest Hard Answers. He can be found in The Frozen Hearth, in Winterhold.

Niranye in Windhelm - owns a shop in the market just outside the white phial. Becomes available after the quest Summerset Shadows.

There is a quest you do for Tonilia where you gain the allegiances of the Khajiit caravan that wanders Skyrim. Afterwards they will also act as a fence for you, although this is less usefull than those listed above as the caravan's location is constantly changing. The quest isn't showing in my list of completed quests so I'm assuming it's a miscellaneous quest.