iclaud on osx 10.6.8

You can only make very limited use of iCloud on Snow Leopard: basically you can set Mail up to access email on an iCloud account which has already been set up on a complaint device:

Entering iCloud email settings manually in Snow Leopard or Leopard

Note that you cannot open an iCloud account on a Snow Leopard Mac. This is the situation with Snow Leopard and existing iCloud accounts:

• You will be able to access email and calendars on the iCloud website at http://icloud.com provided your browser is reasonably up-to-date.
• You will not be able to sync contacts or bookmarks from a pre-Lion Mac.
• You will be able to enter the server settings for email manually in the Mail application and access your email.
• You will not be able to sync your calendars directly.
• Some people have been able to set up calendar syncing by using the method detailed here - this is an unsupported hack and may not be reliable, and may stop working at some future point.
• Address Book won't sync: this page has a convoluted hack to make it sync which has been reported as working (and as not working by others). I've not tried it.

There are a couple of third-party solutions which may be of interest.

• BusyCal is an iCal-like calendar application with extra facilities: it can sync with the iCloud Calendar while running on Leopard, Snow Leopard or Lion. A single user licence (two machines allowed) is $49.99.
• Soho Organizer can sync Calendars and Contacts with iCloud on Leopard, Snow Leopard and Lion. A single user licence (multiple machines allowed) is $99.99.

(I have no connection with either firm.)