Hi,
You can download a developer edition (that comes with license)
It will be heavily restricted in terms of what you can (think it is single engine\thread and only 25 users)
If you need a license with more flexibility during test contact your sales rep, they should be able to help you out.
As for question 2, my guess is there would be a cost, but only your sales rep. can really help you out here.
HTH,
Simon