OK - I'm willing to transfer one of my servers from IPv4 to IPv6. How do I tell if my hardware/software/isp/etc. is compatible? Where should I get started?
Bug your ISP first. See if you can get assigned IPv6 addresses. Alternatively you can use tunnelbroker.
If the 3 VPS providers I use, two had them available. None of my local ISP's assign IPv6 addresses, even though nearly all hardware built in the last 5 years supports it.