Elvis Costello leaped onto the musical world stage back in the early/mid 1970's with his album, My Aim Is True. You might recall the excellent 'ballad' titled Alison, from back then?
Another one of my favourites by him is Green Shirt. I hope you like it.
Take the 2006 release, The River in Reverse, with Allen Toussaint for example. A soulful, bluesy style CD is a far leap from Costello's 'punk rock' style, but every song is excellent.
Costello is a great talent, who seems to lavish taking musical adventures with different genres, and if you aren't familiar with his music, visit his web site here... to buy some of his work.