This is a very useful article for anyone experiencing deadlock issues with SQL Server 2005.

http://www.simple-talk.com/sql/learn-sql-server/how-to-track-down-deadlocks-using-sql-server-2005-profiler/

I made use of this while tracking down the cause of the following error:

Transaction (Process ID 97) was deadlocked on lock | communication buffer resources with another process and has been chosen as the deadlock victim. Rerun the transaction.

When using Profiler it is important that you don't set too many items on trace in a production environment, this can cause your database performance to degrade dramatically.