The AERC has produced a form that you can use to submit the record of a rare bird to one of the European Rarities Committees.
AERC Form (pdf)
AERC Form (word)

AERC Guidelines for RCs
Minutes of the AERC meeting on Texel 1991
Minutes of the AERC meeting on Helgoland 1993
Minutes of the AERC meeting in Kecskemét 1995
Minutes of the AERC meeting in Blahová 1997
Minutes of the AERC meeting in Lednice 1999
Minutes of the AERC meeting in Hel 2001
Minutes of the AERC meeting in the Danube Delta Romania 2003
Reports of European Rarities Committees (new compilation by Tadeusz Stawarczyk)
Updates to the list of Reports of European Rarities Committees (new compilation by Tadeusz Stawarczyk)