I was looking for setting more comprehensive permissions than what's available out of the box. I'm looking to set up a group where users have the permissions to create/edit lists, pages, libraries but not create sub sites.
This is what the default "contribute" level permission set does. If you lookup the permissions assigned to "contribute" you will notice it does not have the "create sub site" permissions.
Microsoft has ample documentation available via Office.com, Technet, and MSDN on how to do this, along with a ton of 3rd party blog posts when you do a search for "SharePoint Permissions"
Start here for description of the permission items: http://technet.microsoft.com/en-us/library/cc721640.aspx
And here for how to configure custom permission sets: http://technet.microsoft.com/en-us/library/cc263239.aspx
Rob Finney provides a downloadable spreadsheet showing the defualt permission levels an dpermission sets. http://blogs.msdn.com/b/uksharepoint/archive/2010/10/20/updated-permissions-permissions-spreadsheet-for-sharepoint-2010.aspx