While each list has a disclaimer stating essentially that the list is a courtesy, not an endorsement... known lists are:
- NAGC, and its state allifiates
- SENG
- Hoagies gifted education page (link- http://www.hoagiesgifted.org/psychologists.htm)

To learn more about a particular office or individual you may wish to use a search engine. For example, there may be youtube video interviews, blog posts, etc which may help families assess a comfortable "fit".