Do you mean the US Marine Corps or the Royal Marines? I don't want to assume anything, so I'll give you information for both.
On the Royal Marines website, go to the "how to join" page by clicking the following link - http://www.careers.royalnavy.mod.uk/how_…
- This will give you information about joining. If you click either joining as an officer or joining as a rating, it will give you a list of career offices where you can go talk to a recruiter, a phone number, as well as an email link to request more information.
For the US Marine Corps, go to the website at www.marines.com and click on "request more information". Fill in your information and they will mail you a packet.