So, I use Custom Date 1 for "date entered", (which OBTW it has always seemed to me that it's peculiar that this is not a standard field). So after you get done scanning barcodes you go search for:
I.[CustomDate1] is null and I.[QtyInStock] > 0
Then you do Edit, Select all, Quick Change, Custom Date 1, (it will default to today), Make Changes.