Best places to go for assistance with cloud questions?

[Alex]

Hi,

I have a few fc17 installs, and would like to get more involved with
the cloud services that are available. I'd like to know the
differences in the capabilities between fc17/fc18 and RHEL?

Are these clouds primarily for data storage, or can I use fedora as a
front-end where my mail applications (such as webmail and pop/imap)
would access data in an Amazon cloud? This still leaves a single point
of failure in my fedora system, however.

Where can I go for basic information on the process involved with
setting up such a system? I've read the fedora "cloud guide" draft,
but it's still lacking significant bits of information, and is
specific to a relationship with Amazon.

What is the difference between OpenStack, Sheepdog, and Eucalyptus?

I'm trying to create a fully fault-tolerant mail system, where if the
front-end webmail system or the back-end spam/virus processing, or
even the mailboxes, somehow become inaccessible, it is mirrored on
another system and will automatically fail over to that system.

Is there a single product that will do this, or do I need to master
all of the above programs?

I'd appreciate it if someone could point me to a discussion on the
different technologies, and a description for an advanced admin to get
started implementing this solution.

Thanks,
Alex