I can find the Team ID for a registered development account by going to:
developer.apple.com > Account > Membership > Team ID
I'm sure that a similar ID exists for the Personal Team. If I select my personal team in xcode and then open MyProject.xcodeproj > project.pbxproj, I can find said ID by looking for DEVELOPMENT_TEAM. But this is a rather hacky way to find my personal team ID. Are there other simpler ways to find it?