Register for Gmail directly using proxy servers from Australia, etc.

Gmail is currently invitation-only in most countries and regions. The U.S. was the first to allow mobile phone registration, and not long ago, Australia and New Zealand also enabled invitation-free Gmail registration. Owning a U.S. mobile phone and sending a registration text message from the U.S. can be challenging, but it's much easier to disguise yourself as a user from Australia, New Zealand, or Japan online. You just need to use an Australian or New Zealand proxy server to access the internet.

(Australia, New Zealand, or Japan all allow free local registration.)