I don't know the backstory or anything, but a man by the name of Rogelio Reyes Cannady, who is on death row, has been "blogging" (or, at least, sending hand-written blogs to somebody for publishing). You can read them here:
http://deathwatchjournal.wordpress.com/about/I haven't actually read more than "day 1", but it's definitely an interesting concept, and can give you a good idea of what a prisoner's life is like.
I told him how I felt about myself and my circumstances after all these years: I arrived in prison as a misguided teen-ager. Today I am a grown man, different. I would like to be left in peace to deal with what is before me. So much is uncertain and I only know that they plan to execute me in 76 days’ time. I plan to live as fully as I am able.
<edit> tracked down what his crimes were:
On October 10, 1993, Cannady fatally beat prison cellmate Leovigildo Bonal. Because Cannady was already serving two consecutive life sentences for two murders committed in 1990, Bonal’s murder was a capital offense. Cannady beat Bonal with a combination lock attached to a belt and repeatedly stomped and kicked Bonal in the head with boots. 55 years old at the time of his death, Bonal was serving a 15-year sentence for a Tarrant County murder.
Cannady has a long history of juvenile offenses that began in 1984. In addition, on December 10, 1989, when Cannady was seventeen years old, he committed a robbery in Harlingen, Texas. While he was out on bond for that crime, on June 29, 1990, in La Feria, Texas, Cannady fatally stabbed Rick Garcia, a fifteen year-old-boy. On the same day, Cannady sexually assaulted Anna Robles, a thirteen-year-old girl, then helped strangle her. Cannady was tried and convicted of the robbery charge in September 1990, and sentenced to 20 years in prison. Though Cannady was originally charged with capital murder for the double homicide, in exchange for his guilty pleas, the charges were reduced to murder and he was sentenced to
So there you have it, not what you'd consider a good person.