It is a defacto standard process these days to sign up for a 30 day CRM 2013 Online Trial for various purposes – testing a new solution, doing a demo, some ad-hoc experimentation or as a possible go live project.
However, if you go to links like the following, they won’t actually get you there very quickly or make it very hard to figure out how to kick off a new instance:
1. http://www.microsoft.com/dynamics/
2. https://community.dynamics.com/
The link to use and book mark is: http://www.microsoft.com/en-us/dynamics/crm-free-trial-overview.aspx