A lot can happen in a year. About this time last spring, an unsigned band out of Australia, the Temper Trap [pictured], was one of the big buzzes of the South by Southwest Music Festival. Now the London-based band with the big, anthemic sound is riding a wave of support for its debut album “Conditions.” With a Coachella appearance in the distance, they headline the Fonda Theatre tonight, with local quartet Darker My Love (sure to play some material from its forthcoming third album) supporting. … Long Beach’s Delta Spirit has completed work on its sophomore album for Rounder. No release details yet, but it’s quite a leap from “Ode to Sunshine” (if I hear a better folk-rock album in 2010, I will be surprised), and the quintet has a sold-out show tonight at the Bootleg Theater, with We Barbarians opening. … Also: Cary Brothers and Meiko at the Hotel Cafe; Little Boots, Dragonette and Class Actress at the El Rey Theatre; Olin and the Moon and Correatown at Club NME at Spaceland; Kissing Cousins and Wet & Reckless at the Silverlake Lounge; Abe Vigoda and the Black Apples at the Echo; Free Moral Agents at the Airliner; the new venture from Travis Barker and A-Track, Travis x A-Trak, at the Roxy; the second night of the sold-outÂ Manchester Orchestra/Features bill at the Troubadour; Brian McKnight at the Key Club; Walk the Rio at the Viper Room; Learning Music at Echo Curio; Great American Taxi at the Mint; and Twin Tigers at Alex’s Bar in Long Beach.