The basic Yorkshire pudding recipe is simply mixing some eggs, milk and flour and beating until really there is a lot of air in it - like you were making a cake, but with the milk, it won't get as thick and ribbon like a cake batter.
I'll look in my Beard book as well but there are a ton of recipes on the web - the tip/trick that I have(from Beard) for this is to preheat the oven to 450F, while you're making the batter preheat the dish. Then when you are going to make it, pour 1/4 cup of HOT beef fat, taken from the roasting pan and kept hot, into the dish and then pour the batter in afterward. You may want to keep your guests out of the kitchen when you do that. I have had many ask "why is it so good" and "how do you make it" that are later astonished that they ate something with so much fat and eggs in it, to which I always respond - hey it's only once a year, etc.. BTW I remembered that I posted pics of a rib roast and Yorkshire pudding on page 5 of this thread.
Au jus is nothing more than the roasting pan, drained of fat, deglazed with beef stock. If you are going to do this I HIGHLY recommend that you make your own beef or veal stock - again, ask for recipes. An alternative may be if your butcher makes and sells it, or you could try
http://www.gatewaygourmet.com/demi.htm gateway gourmet - the only concentrates I have ever found good enough to use.
Thanks for the compliment - cooking is one of my favorite things to do. I really like the creative release and it enables me to have fun and "spread the love" to people at the same time.
Oh, another tip, if you cook the roast rare, if anyone wants it more well done it's an easy task to put some into hot stock for a minute or two to cook it some more without drying it out.