Ashi, that is a tough question. I usually work my way through the annual list of the Edgar Award winners. They give awards for the best novel, best first novel, best true crime, etc. I just finished one called Fake Like Me by Barbara Bourland--I thought it was fresh. If I had to choose, I always read anything by Caleb Carr, James Elroy or Erik Larsen (who does more history, but the Devil in the White City, set in my hometown of Chicago, was a great true crime book). I'm reading one right now by David Patterson--it's about John Lennon and Mark David Chapman. It's called the Last Days of John Lennon.
I really like true crime. The first true crime novel I ever read was Helter Skelter by Vincent Bugliosi--I was on vacation and hated being there (because I was a teenager) so I just read the whole trip and ignored my family. I think I also read In Cold Blood by Truman Capote that vacation. Then later I read Fatal Vision by Joe McGinnis which introduced me to forensics. You can tell I was a very cheerful teenager. :)
Tell me your favorities!