I am posting this because I spent many hours rooting my G1 using the old downgrade to RC29 method before I found out that there is an easy to do it.  Easy way: http://theunlockr.com/2010/09/23/how-to-root-the-htc-g1-dream-androot-method/

I love theunlocker.com they have put together a quality site for unlocking all sorts of phones.