Where does virt-manager store config files?

Oddly enough, under /etc/libvirt. virt-manager doesn't run as root, but it communicates with libvirtd that does.

Client information (eg connection strings) is stored in the dconf (accessible with dconf-editor) under /org/virt-manager/virt-manager/.

virt-manager config is on

~/.gconf/apps/virt-manager/