We get our IP's from RIPE, which is the European market for IP addresses. We then transfer and geo-locate our IP's over to the US and announce the IP's at the US datacenter.
The announcement takes a couple weeks to geo-locate the IP addresses. Please make sure to use proxies for optimal speeds. Note that amazon and some other databases only update every 6-12 months.
Note that your server is in the location of sale. If you buy a VA server then it will be a server physically located in VA.