Its strange really as VHDL is a subset of ADA95 which is a US DoD project and yet VHDL is mostly used in Europe and just to be difficult the US and Asia use mostly verilog.Anyway I thought rather than sticking in random bits of code there is a very good intro to VHDL and a step by step design of a pipelined 32 bit processor
at
ftp://ftp.cs.adelaide.au/pub/VHDL-Cookbook/
which I took a lot of ideas from.