You can quickly choose what location you would like to search by going to the home page and selecting the magnifying glass in the top right corner.
This will bring you to the search criteria page where you can select which category you want to search in, and what you are looking for. From there, you can add in a new address, or use the map to drop the pin on a new location. You can also adjust the radius of where you are looking.
Once you have entered all of your search criteria hit the start looking option and you are good to go!
You may also change your location when you enter an item's showcase. Simply scroll down until you see the map, and you can change the location in order to see how far away you are from it.