Steven Price was a holographic character in a program set up by The Doctor to teach Seven of Nine social graces.
He was a customer at Sandrine's who Seven offered to buy a drink for at the urging of The Doctor, so she could practice her social lessons. While observing their interactions, Tom Paris noted Price's unflappable acceptance of anything Seven said about her ex-Borg drone status. He felt The Doctor had programmed Price too flawlessly, and that real people would not respond as he had.
After a few minutes of conversation, Seven announced to Price that she had mastered the art of small talk, and would now end their encounter. (VOY: "Someone to Watch Over Me")
Steven Price was played by actor David Burke.
Price's name was not given in the script, rather, he was described as "The Regular". The script also notes that his beverage was a scotch.