this is what i did (syncing 1 x laptop, 2 x google accounts(mine and my wifes) and 1 x ipad.
i will take that you should know how to set up accounts on all devices but if not let me know.
1.Setup 2 google accounts and sync those accounts together.
2.Download google sync for your Pc and sync it to one of the google acounts.
3.Using caldev on the ipad create an account to link to one of your goggle accounts.
4. sync accounts using this link https://www.google.com/calendar/iphoneselect
5. On your ipad under settings go to your calendar and choose gmail as default account.
it's very important that u choose gmail calendar account on the ipad or it will not work.
this will work and now no matter where i put a event in the calendar on either account it will sync over the 4 devices.