Expired Green Card & Outside the US

[achtung]

Hi,

I am a GC holder since 1996; the last time I was in the US was 2002; I had to return to my home country due to family commitments and have been unable to return. My Green Card expired in 2006 and due to the circumstances could not pursue the renewal as well.

I am now wondering how to renew the GC and return to the US as I understand that the re-entry is valid within certain timeframe of GC expiry? Would appreciate if anyone could guide me in this regard.

thanks...