Dude. You just need to read. All of these questions could be answered by reading threads on this and many other forums, as well as even just looking through a Dr. Foster's and Smith catalog, or viewing their website.
i agree that reasearch is the best way to go but dont ever feel pressured not to ask questions. maybe start a new thread for each though. and careful with Wiki its not always correct, but general ideas are usually fine.Read and find my freind, that is the beauty of the internet. Maybe start off with wikipedia.net to find a broad array of questions and then ask something still un answered instead of using up forum space Also visit your LFS for advice and price estimates.