VISIT FROM A SMALL PLANET: Indie label Planet LA will hold an after-party and benefit concert for Japan earthquake relief on April 30, from 8-11 .m. at the Cabana Club in Hollywood (next to Amoeba Music) to coincide with the close of the ASCAP Expo. Free admission to all early RSVPs or anyone who mentions HITS magazine. Also involved are music companies Line 6, Blue Mics and MusicBox, among others. The event will be broadcast live by StageIt.com, To RSVP, contact Planet LA's Mark Nguyen ([email protected]). (3/31p)