THEY’RE BOOKED: The CMJ Music Festival is in town, so the Housing Works Used Book Café is holding a special afternoon edition of its acoustic benefit series today, with a stellar lineup that includes Detroit’s Brendan Benson, along with Blanche and Buck 65 (a k a one-time pro baseball prospect Rich Terfry). Mercury Rev’s new album, “The Secret Migration,” will be played between sets – its first public presentation. Showtime is 2 to 4:30 p.m.; tickets are $7. Housing Works Used Book Café, 126 Crosby St., between Houston and Prince Streets; (212) 334 3324.