Tell him to sit in at open mic nights and hang out with every solo artist he can find. Watch and learn. Then, when he's ready, he'll have an idea of who went over best in his travels. Working a crowd is a natural gift, as is singing. You can teach breathing and diction, but not singing. Best singing lesson I ever took was studying clarinet. It taught me phrasing, articulation, dynamics .... it's all there.

As for gear - a laptop, ipad or even ipod will do the trick, but the larger the item - the more complicated the setup. Personally - if I ever started just singing over tracks ... I'd use a DJ style controller linked to a laptop ... and into a BOSE, of course.