Well, if you're in the U.S. you don't need to know all that, "downhill three left minus slippy" stuff. With rare exceptions, we don't use pacenotes here. Co-driving is MUCH easier in blind (non-pacenote) rallies. Judging by some of the moron co-drivers I've seen who have never even read the rulebook, there aren't too many barriers to entry!
Pick an event near you, and post on the co-drivers section at specialstage.com that you're a novice looking for a ride. Download the ProRally rulebook from
http://www.scca.org/amateur/performa...ly/02rulebook/ and read up on timing and control procedures so at least you'll know the basics. Your driver will tell you how he wants the routebook called anyway.
Good luck!
Jon
www.rallystuff.com