One caution on the AOS cultural info (such as the culture sheets) - they are very general, and tend to have a south Florida bias. For genera such as Phalenopsis that are all pretty much the same in cultural needs, pretty accurate. But other groups (such as Oncidium, Cattleya, Dendrobium, Pleurothallid) you have to get down into the detail of your particular plant to have a chance of getting it right. (In fairness, they do have a Dendrobium document that lists the major sections, with their needs, individually - the "general" sheet is pretty useless if you don't have a phalaenopsis-type Den)
Also, when you buy a plant, ask the vendor. If they have actually grown the plant, they are likely to be able to tell you something about its requirements. If they hesitate, or appear to be giving generic advice, they probably bought the plants wholesale shortly before the show and don't have a clue. If you order from the major growers on the Web (there are lots of mentions in the Forum about people's experiences) you can also learn a lot if you ask - but again, you have to filter the advice through the lens of your own conditions. The more that you can learn about the natural origins of your plant the better you will be at figuring out how to make your environment work for it. (Orchids can adapt up to a point, you want to get as close as you can to what it actually wants) For species,
Internet Orchid Species Photo Encyclopedia is a fantastic, and free, resource (read the descriptions, don't go by the icons which often don't match the text), for hybrids learn about the parents if you can, because it all goes back to the species.