Banes World Bucks or BW are the in game currency that can be used in the UO Store to buy luxury items. You can get BW by doing achievements. just use command [myachievements. Many of these are as simple as visiting various places that can be done by using the portal.
You can also earn BW by completing daily quests at the huntmaster's lodge. Under favorites on the portal system.
You get BW by donating to help maintain the shard. Every donation is greatly appreciated and used to maintain and pay the cost of the server. There is a blue donation stone in mainstreet. Once you donate you will get a pop in game to claim your BW.
You can access the store by the UO Store button at the top of your screen. You will need to be in a safe place like an inn or your house. You can also use the command [store