Every year since 2004, the Atlanta Gallery Association's 21 galleries have thrown a gala to help spread the word that, hey, there's art out there, and it's for sale. ARTHOUSE, ATLart's annual kickoff Sat., MAY 5, takes place in a $4 million, 12,000-square-foot Ansley Park mansion. Art works (right) compete for attention with wine cellars the size of garages and other holy-cow details of how the other half lives. This year a percentage of ARThouse's ticket sales benefits nine Atlanta public high school arts programs through the inaugural ATLart Foundation. Opening gala: $175. 7-9 p.m. ARThouse exhibit: Through May 27. $10. Wed.-Sun. and Mon., May 28, 10 a.m.-5 p.m. 1640 Nottingham Way. 404-846-8255. www.atlart.com.