Hm, it's a bit misleading but you don't actually need a verification Email or account to download GameMaker. From the main YoYoGames website, click on Get GameMaker, then click on the Free Download button on the next page. It will then take you to a page prompting you to make an account, ignore that and scroll to the very bottom of the screen, there you should see some underlined categories like "GameMaker", "Download", "Support", etc. Under the "Download" category click "GameMaker: Studio" and it should give you the download for the installer. For convience, here's a direct link to the download [link].
I don't have a great deal of experience with GameMaker compared to Python so I may not be able to offer much help, though I have found a few tutorials for making First Person Shooters that may prove useful. If on the other hand you want to try Python you can read Learn Python the Hard Way, it has a similar syntax and format to Scratch and serves as a good gateway to other lower level languages. There's also an open source Minecraft Clone written with Python and Pyglet over here.