I think this same thread came up last week. Basically the same answers too.

To the OP: There is a alot of information available about RC airplane design. Some good stuff online, and lots of good stuff if you're willing to buy a book. If this is just for you to have an airplane to enjoy, then buying an ARF or RTF plane is the cheapest, safest, and easiest route to go. It would be smart to at least start with a proven design and learn flying before trying to design and build something from scratch.