Console commands are, in fact, PC only: PS3 and Xbox 360 owners do not get access to the console. If you sell an item and the merchant resets their inventory (usually after reloading the game), the item is lost forever. Your only solution is to load up an earlier save file.
Windhelm probably offers the highest convenience factor. The market neighborhood, directly to the South, offers access to a full set of outdoor smithing equipment, as well as an Arcane Enchanter, at least three 'high-value' merchants (two general goods, including Niranye who is a Fence, and a Blacksmith), all without a loading screen. The house itself offers both Alchemy and Enchanting facilities, as well as the highest number of display racks for equipment of any home, and Windhelm offers an additional battery of merchants over in the Grey Quarter on the eastern edge of town.
Downsides include the somewhat high price, long distance from Windhelms fast-travel point, the prolonged string of quests required to buy the house (you basically must resolve the civil war), and the potential for significant bugs related to the Blood on the Ice quest, in which the house is involved.
Riften deserves an honorable mention for Thieves Guild members. While it lacks smelting services, the upgraded Ratway, with it's 4 additional merchants, puts somewhere in the neighborhood of 12,000 Merchant Gold in close proximity - easily the most of any city. Those who choose to take the moral high-ground may find the mercantile climate of Whiterun to be more hospitable however.
Best Answer
Expanding on my comment that there is no way to search for an item in the game*.
One answer is to use console commands to add the bow to a known merchant then manually buy back the bow from the merchant. You might want to do this with a merchant who is likely to have acquired the bow naturally though any merchant will do.
First you will need to find out what the FormID of the bow is. To do this you will need to load a previous save where you have the bow. Open the console and run:
The bow will be listed with it's FormID being enclosed in brackets after the name.
(I think you can also just drop the bow and left click on it?)
After you know the FormID load up your current save game and find the merchant you want to give the bow to. Open the console and left click the merchant, running:
Close the console and buy the item from the merchant as normal.
If you ever encounter the "real" bow then you should remove this from the game by selecting the merchant and running:
*The toolkit or a custom mod may add this, however they are not released as of this post.