How do I find a particular seller?

1. To find that particular one who's member name is arohashop you can search for "Arohanui Hospice"

Found it!  I had the wrong name, it's not Arohanui, it's Aroha Shop.

Kia ora scarlettohara, you can find a list of all Trade Me stores here, you can navigate to there from the Trade Me home page, click on Marketplace (under the search bar). On the next page under the Trade Me logo you'll see Browse Marketplace and stores - click stores. There is also a search function for stores on that page but you'll need to know their store name to do that.