Hello. 400D owner here. I agree with these gentlemen i.e. your lens might be having some problems. I've yet to experience the problem you are having on my unit. As for the kit lens being rough i.e. grinding feel, is actually normal with Canon kit lenses (experts: correct me if I'm wrong here)...
Hi newbie here. Great community!
Akihabara is one place to start looking. Lots of gadget/electronics/camera shops. Good deals can be found to. Yodobashi has a huge store there AFAIK. LAOX also has its own camera branch. Last time I was in Japan was 2002 - got myself a vidcam from LAOX and saved...