Please can someone create this addon or tell me how to find it I cant find anything like it:
Can you create an addon that will allow you to type out a character name and then will tell you which servers that character name is not taken on.
And you will be notified if at any time a character name becomes avaliable.
Such an addon isn't possible. You can only check for the availability of names on your current server, eg. by trying to add the name to your non-Battle.net friends list. Just type "/friend Thenameyouwant". If it says "Player not found" then the name is available.
While it would be possible to write an addon that automatically did the above to notify you if/when the name ever became available on your server, it doesn't really seem worth writing or using, since the odds of someone renaming/moving/deleting the character with the name you want are so low.
If you want to check other servers, you have to create a character and log into them.
You can also search for the character name on the WoW site, but if it doesn't show up in the results, that's not a guarantee it's available, since low-level characters and characters that haven't logged into the game in a long time aren't shown on there.