The best way to learn about the great figures of antiquity is to read the ancient sources from which our knowledge is derived. With regard to Pyrrhus, I would contend that the best starting point would be Plutarch's Life of Pyrrhus. I realize that some might not consider this "layman" reading, given the various references to names and events that a layman would not be familiar with but I think the overall narrative is clear enough. Plutarch always makes for interesting reading and he gives you a good idea of the wild and wonderful adventures of Pyrrhus. However I should mention what any worthwhile classicist will tell you, namely that Plutarch was more of a moralizing biographer than he was a historian. Simply put he was, by his own admission, not writing serious history. This doesn't mean that we should discard him as he certainly remains a valuable source, but take the fanciful anecdotes that dot his work with a grain of salt. He was also writing in the first and second centuries AD, long after the events he describes. Unfortunately the sources regarding the time Pyrrhus lived were written by non-contemporary historians and Plutarch is just one example. Again, this doesn't mean we should discount them but we should still take it into consideration.

In terms of secondary source literature the most recent biography is Pyrrhus of Epirus by Jeff Champion. However I have not been able to get my hands on a copy so I can't speak for its quality. For other secondary sources try looking at the relevant sections of broader works concerning the successors of Alexander the Great as Pyrrhus features prominently in their later conflicts. For a very readable introductory work on this topic try Dividing the Spoils: The War for Alexander the Great's Empire by Robin Waterfield.