A TON of info on this.
The DIY section has an overview of how to detail a car called 'Lee's Detailing FAQs'.
Mike Philips of Meguiar's has posted a number of threads linked at the following thread. Some of these discuss use of poly coats as well as traditional waxes.
http://www.peachparts.com/shopforum/showthread.php?threadid=48046&highlight=Gold . Meguiar's also has a web site with a tool that guides you through surface prep and waxing for your car.
A search for 'Zaino' will give a lot of info on those products.
If you don't have scratches or swirls, you may not need machine polishing - this always removes paint. My 87 300E has never been
rotary machine polished. It has been maintained with an
orbital buffer, which is much less aggressive than rotary machines. At the Meguiar's clinic I learned that if you have never used a rotary, don't start out with anything you like, as you can burn right through the paint. An orbital won't damage the paint, but won't work real well on scratches. If you do have scratches and lots of swirls, you may need a rotary buffer in the hands of a skilled professional, or done yourself after lots of practice on something that doesn't matter.
Clay takes stuff off the surface, not out of the paint, and I have never heard of it staining paint. Unless it feels smooth as glass, you could benefit from clay. If not used properly with a decent lube it can streak. If used when dirty the dirt sticking to the clay can scratch. A new bar of Clay Magic with lots of Final Inspection spray used as a lubricant WON'T streak.
Oxidation will need to be removed, but may not need a rotary buffer for this - there are a number of products that remove oxidation - check the Meguiars web site or call their 800 number.
Good luck, and enjoy your car!