I applied online. The process took 4 weeks. I interviewed at Currys (Rugby, England) in Apr 2013
Interview
The interview mainly comprises of questions geared towards customer service and selling to customers. Technical knowledge would definitely improve your chances as working on the Knowhow bar involves diagnosing computer faults and answering customer's questions.
Despite it being customer service it still is a retail orientated interview. If you've had previous jobs in retail this interview should be a familiar experience.