There are lots of topics about detailing products, including some by me. As the Forums Nazi would say, do a search and they'll pop up.
I think that people are often too hung up on asking about brands rather than processes. While I have my own preferences (for various products from Zymol, Meguiars, and Clay Magic), I think you will get great results if you concentrate on a process, rather than which brand is best. The best process to give your car that showroom shine is a multi-step process. Depending on what kind of condition it's in, you will need to consider steps that include (a) washing it (obviously); (b) addressing any specific problem areas (such as removing tar or bird droppings with a solvent, and/or buffing down serious swirl marks or scratches with a swirl mark remover or fine compound); (c) removing surface contaminants with a clay product; (d) removing oxidation and light scratches with a non-abrasive cleanser or polish; and (e) applying a wax layer to protect the finish. I think going through this entire process on the car once, and then periodically using whichever products are needed to keep it looking good, will give you the best approach. And I think you can do it successfully regardless of whether you choose the Zymol products at a small number of retailers, the Zaino products sold through private distributors, or the Meguiars or Mothers products you can find at your neighborhood auto parts store or big discount store. I think you'll find a much greater difference between people who use all these steps, and those who don't, than you will between people who use all these steps for one brand, and those who do so with a different brand.