How can I find my Apple Developer Team id and Team Agent Apple ID?

You can find your team id here:

https://developer.apple.com/account/#/membership

This will get you to your Membership Details, just scroll down to Team ID

You can find the Team ID via this link: https://developer.apple.com/membercenter/index.action#accountSummary

If you're on OSX you can also find it your keychain. Your developer and distribution certificates have your Team ID in them.

Applications -> Utilities -> Keychain Access.

Under the 'login' Keychain, go into the 'Certificates' category.

Scroll to find your development or distribution certificate. They will read:

iPhone Distribution: Team Name (certificate id)

or

iPhone Developer: Team Name (certificate id)

Simply double-click on the item, and the

"Organizational Unit"

is the "Team ID"

Note that this is the only way to find your

"Personal team" ID

You can not find the "Personal team" ID on the Apple web interface.

For example, if you are automating a build from say Unity, during development you'll want it to appear in Xcode as your "Personal team" - this is the only way to get that value.

For personal teams

grep DEVELOPMENT_TEAM MyProject.xcodeproj/project.pbxproj

should give you the team ID

DEVELOPMENT_TEAM = ZU88ND8437;