To manage the list of sites you wish to list on, follow these steps:
Click on the menu option:
Tools > Options > Sites
A new view will open on the right hand side as shown below:
Check the boxes against the sites you wish to list on.
Clear the boxes against the sites you no longer wish to list on.
Finally, click on the button "Save" to save the list. If you added any new site, Wonder Lister will fetch your data from eBay and update its local database. It is highly recommended that you close Wonder Lister and reopen it for the changes to be reflected all across the user interface.
Notes:
The number of sites you can list on depends upon your subscription level.