You cannot know who the previous owner was. At least not through any code.
As for seeing where they are there is a show on galaxy map and some other stuff like that that should show where they are. If they are not lying on a planets surface (which would give you exact co-ords) then you will probably have to go to the Traders Lounge and ask to see if anyone knows where, or who owns the entity your stuff is docked inside.
Thats morning for us living in aussieland. Anyway Jevon, I have a sneaky suspicion that that regularity was something that was changed. Apparently it wasn't random enough in when stuff went to the market, which could be that it went at the same time of day, but on different days. So its possible that it has since been changed to show up at a random time of day as well as actual day.
But don't quote me on that, I am just guessing unless others have evidence to the contrary (or supporting).