Create a Sugarcrm/phpscheduleit connector
When a contact, or meeting is created or updated in sugarcrm it is created or updated to the appropriate schedule and resource in phpscheduleit.
When a contact, or meeting is created or updated in phpscheduleit it is created or updated to the appropriate user and calendar in sugarcrm.
Preferably the sync would be automatic, however it could be ran a cron job, or manually syncing if absolutely necessary.