There are several artists using this name: (1) Costello is an Irish hip hop emcee and member of Street Literature. His music has been released by Workin Class Records and his debut album Illosophical has received national praise for its sophistication in rhyming and superb production contributed by G.I. http://workinclassrecords.com/
https://www.facebook.com/pages/Costello/273706839350000 (2) Costello is a 4-piece melodic punk/power pop band hailing from Los Angeles, California.

Read more about Costello on Last.fm.