Hey Lieven.
I AM a producer - not one of these current types who aren't musical enough or technical enough to be either a musician or an engineer but want the respect/glory that goes with the title, but someone who can bring a project together on time and on budget.
The skills required are a knowledge of studio engineering (I used to teach 3rd year degree students who knew nothing more about recording than using a computer how to be engineers in a professional studio where a computer is only part of the set-up), a knowledge of the media you are doing the project for (I've done film soundtrack, radio play soundtrack, actors vox demo (basically spoken word recording including dummy radio adverts, extracts from talking books and voice-over for things like corporate training films) and musical projects ranging from classical solo recordings and religious music to hardcore Hip Hop and I haven't done everything!!!) an ability to inspire/excite a performance (I've used drama games/exercises to get THAT performance), a love of whatever you're working on and a good knowledge of music (I've created complete orchestrations for solo artists based only on piano score) if working in that field.
I came up with an adage about producing - "The art of being a good producer is handling being a control freak. The art of being a GREAT producer is no-one knowing you are a control freak!"
I hope this answers your first question.
For the second: a, Think of a band you really like who've done more than 2 albums and decide which you think is the best album. Look at the album credits under producer and there's your answer. b, Find names of producers and a list of their catalogue of work and work out who's done more albums that you really like. c, Let other people tell you (cop out answer).
As a producer, Simon Cowell knows what works/sells but I've heard that he registered with the Musician's Union as a triangle player to get musician royalties from his projects as if the producer's fee wasn't enough and I've never heard of him being alone in the studio with an artist and no engineer(s), tape op(s) etc - says it all!!!
<-----<< On an even field, only talent prevails! >>----->
Gans Gwarak da yn dorn yu lel, gwyr lowen an golon!
>>-----> [color=#FF0000]Rudhes[/color] hag [color=yellow]Owres[/color], Kajima <-----<<