Mizuno makes a couple of nice youth catcher's mitts in the Prospect line. In my estimation they are appropriate for youth ages 7-12. The GXC100 is a closed web closed back mitt and the GXC110 is a closed web open back mitt. Both have the V Flex innovation, essentially a notch of leather removed from the hinge that allows a young hand to fully close a mitt. See http://www.mizunousa.com/equipment.nsf/ ... thcatchers
or if the link does not work try mizunousa.com, follow the baseball/softball links, gloves, youth, catchers.
If the child has to have a catchers mitt, either required or by desire, these would be good serviceable mitts (my 9 year old has the GXC100) but most kids that age (farm league i.e. coach's pitch) actually catch better with their own fielders glove than a bulky catchers mitt. The point is, at a young age they can play the position with their fielders glove and do a better job than with a youth sized catcher's mitt.