Q:

What are good things to look for in formulas for newborns who need to supplement? 

What sort of formula should I look for for a very new newborn that doesn't promote constipation? 

A:

Honesty, Enfamil has been highly recommended to us by a few doctors as having the closest to breast milk nutrition.  They have several different types, we personally use the Infant AR formula with Dr Brown's bottle line.  You can sign up with them and they will send you a pack of coupons for $4 off a package.  
http://www.enfamil.com
Check this version out: http://www.viewpoints.com/Enfamil-Gentlease-Infant-Formula-reviews
On another note.. lets say the formula isn't the issue and your baby is just having a rough time and you want to help them out.. I massage my baby's belly to help her.. I also lay her on  my chest with her on her back and I stretch out so she is arched.. It seems to really help her relieve herself.  Here is some good resources that may help you help your baby :)
My Massage, I roll my fingers on her belly like I'm doing the wave on her lower abdomen, then I press down a little firmly when she starts pushing to help "squeeze" it out.  I have stomach issues myself so I try thinking what I do when I am having issues and I apply same principle to her but in smaller scale.  
I also mover her legs like she is riding a bike, or I put my hands on the bottom of her feet and let her push on them really hard.  I stretch her legs out and push them back in and up so it kinda rolls her in a ball.  In my head I invision that I am trying to "reform" the poop to a smaller or longer shape that will allow it to exit easier.  
Helping her poop when she is having issues is one of my responsibilities and I think I do it pretty good :)
Massage: http://www.youtube.com/watch?v=vseuKsNGmXs
http://www.liddlekidz.com/massage-for-constipation.html
http://wholesomebabyfood.momtastic.com/constip.htm

