All of these servers used to be hosted on Zone.msn.com as part of the publishing agreement with Microsoft. Turbine bought back all franchise rights from Microsoft in 2003 and consequently took responsibility for server hosting. The servers remained at a facility in Washington State until 2008 when all server hardware was replaced and relocated to a facility in Massachusetts near Turbine headquarters. Due to various quality of service issues that caused extended downtime the servers were moved to a new facility on March 30th, 2009.
The Asheron's Call Beta servers were hosted via the MSN Gaming Zone.
Beta World Red was the Beta 0/1 server - the first world to be be brought online for the Asheron's Call Beta.
Beta World Green was the Beta 2 server. It was online from 08/03/99 to ?? and was announced as having "many new features" over the previous red world.
Beta World Blue was the Beta 3 server and was open to the public. It was online from 10/18/99 to 10/24/99 and was using the new September game build.
This server was available for all players initially from the 26th of April 2003 to 28th of April 2003 to stress test some new server hardware. The character database was an exact copy of Solclaim, hence the name Shadowclaim.
Original Link: http://zone.msn.com/asheronshadow/default.asp
This server was available for all players from 06/22/05 to 07/12/05 as an open preview of the upcoming expansion pack Throne of Destiny. The character database was an exact copy of Leafcull.
This server opened October 4rd, 2008 after being delayed a day and remained open until October 6th, 2008 to stress test new server hardware. The character database was an exact copy of Frostfell.
Internal Test Server
As mentioned in numerous posts by developers, Turbine has an internal test server. It is currently not available for players, supposedly. There has been some active players granted access to the test server to test content prior to it being delivered to the general player base.