Always check Note2 when you suspect a duplicate. One is the regular version and the other is the Glossy version.
Ad Cards have been lumped into their own set, since they were made & released without set affiliation. Promos, on the other hand, were always released 1 promo card for every 5 sets purchased from Star Co., so they are going to be listed with the sets they were associated with.
-- Dan --
Note: Please see my profile for more info regarding trading (section updated 3/4/2024). I have added a large portion of my inventory to the site, and currently have trading turned on (details are in my profile).