Hitler had several Fw 200s during the course of the war. Most famous is a Fw 200 V3 (A-0) called Immelmann III (D-2600, later WL-2600 and 26+00). WerkeNr = 3099.
Another machine used by Hitler is Fw 200 C-4/U1 with registration CE+IB which wore full east front winter Luftwaffe markings. I'd have to look up the WerkeNr. if it's known at all.
"Grenzmark" was a Führer escort aircraft with WerkeNr. 3098. It crashed on 23 Dec. 1941 in the Soviet Union.
More here (in German):
http://www.flugzeugforum.de/forum/showthread.php?t=6637