Well its suprising the number of idiots who DO turn up for interview without polished shoes. When I was interviewing I noticed every time (non-aviation jobs) and one can't help thinking that if Candidate X cannot be bothered to spend 5 minutes with some Kiwi then how concientious is he likely to be if you hire him?
Darkish suit, new white shirt, polished shoes and a haircut would be my advice.
I wouldn't worry too much about clammy handshakes - most interviewers will understand that its beyond your control. Some people have sweaty palms others have vice like palms as arid as Arizona.
I think its also worthwhile to do a litttle research or buy a book about interview techniques and non-verbal communication.
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