Islam discussion

please suggest some books written about the Prophet Muhammad

Muhammad: His Life Based on the Earliest Sources
Martin Lings.

I think Karen Armstong's biography of Muhammad is pretty good.
Muhammad by Karen Armstrong

Check out this site: http://www.mysticsaint.info/2012/08/b...

The good thing is the site even list some pdf reads.

I personally find Martin Ling's Muhammad a good start. But in case you need a more thorough read, try Alfred Guillaume's although it is a uphill task considering the detailed discussion.