D.W.
Dr Alvis, a pedi in McKinney has a spot on his web page about how to pick a pedi- http://www.stonebridgepediatrics.com/making_the_choice.html
Personality is the biggest factor ( I work for 5 different pedi's in one office and all are very different. Talk to your friends who expect similar things from their doc (do you want 24/7 access to the MD or will you be ok talking w/ a nurse, do they have evening office hours? Do they call in antibiotics? etc....) and ask for your frineds referalls. Most Docs will do no cost consults, so I would schedule a couple and just talk with the docs, see the office and go from there.
I am a Pediatric RN. I work in one office on Saturtday's and do call for 11 more at night, so if you have any questions, please feel free to e-mail me.