you can use auctiva to post items to your ebay store, but you have to pick an ebay category to put it in (in addition to your store category(ies)).
first go to my_ebay and select to manage your store. then create the categories you will be using.
come back here and click the MyAccount tab.
then click eBay Settings
then click Update Store Categories from eBay
Now create a listing and in the listing editor select the button labeled Store Item. this will cause your store categories to be available in drop down boxes
you will need to select an ebay category, set item specifics for it, and then choose your store category(ies) to use.
Tip - you can create profiles (using the Profiles Tab) to use over and over. makes it faster to create a listing