I do not have a link but setting up a plar is very easy. for a given partition weather it is for auto registered phones or just a full time plar like a house phone or some thing like that. after you have created the partition for the plar add a tranlation pattern. leave the translation pattern blank set the parftition to the one that you jsut created. set the call search space to one that can call the phone the will be the other end of the ring down. finally change the called party transformation mask the the number of the device that will be called by the ring down. now any device that is in the new partition or devices that have a call search space with the new partition listed as the highest priority will call the number setup in the called party transformation mask of the translation patteren you just created when ever it goes off hook.
hope this helps
scott