I actually am struggling to find a site with Walker's career home/road stats. However, check this out.
Go down to the bottom set of stats and click between home and road. Granted this is not during his prime seasons but the difference is remarkable. Also he was in STL a short amount of this time...I do realize. But the difference is dramatic. During the season that he hit over .350, he hit over .400 at home, and less than .300 on the road.