> That's not exactly designing something, just ripping.
the process of extracting and gathering stock sounds isn't, you are right. however, learning to orgazine a stock sound archive is more important than you might think, because every sound you record and master youself will end up in at least your own stock sound archive. also you are very limited if you want to make sounds just from own recordings. at least i see a problem if i would want to record an industrial metal plate cutter like Ben Burtt did for the AT-ATs in starwars. ^^
anyway. since i mention starwars. this might interrest you, Barney 1337 ;) the following video is a great example about the creative part of sound design, especially if you want to record yourself:
don't let that video deject you from making own recordings, because you now think you need all these expensice gear. you don't. i showed you this video, because the focous like it's said in the video itself is about ppl creating something, being creative. for example all you need to make .50 cal casing sounds is the metal shell of an edding pen and an avarage gaming microphone or something ;)