Yes. You can manage this process using the Administration Site Settings. Simply add users via their e-mail alias and assign permissions such as Reader or Contributor.
Are there any IT requirements or downloads required to set up my SharePoint site?
No. You do not need to download any code or plan for any IT support. Simply complete the on-line signup process and provide us your current and correct email address. Once you have successfully signed up and your site has been provisioned, we will send a confirmation to the email address you provided.