I used to use Outlook on a PC and used the feature to pull emails into todoist and then be able to pull them back up from the task. Can this be done on a Mac without using outlook?
Unfortunately no, not exactly. This can be done through Outlook or with Gmail (with Firefox or Chrome Extensions), or you can actually just email a task.
You can read about the options here. https://todoist.com/blog/2013/01/zero-inbox-policy-with-todoist/
How about outlook on a mac? I noticed the plugin is a .exe file.
Unfortunately, we don't offer any plugins for Outlook for Mac yet, but we will consider developing it in the future and you're welcome to vote for this request in our Votebox: http://todoist.com/Vote/showProposal/275/