[luxstyle]

1 and 2 can be separate, but there are a lot of people whom can do both well. That's not to say that there aren't also a lot of people whom are horrible at one and great at the other. the "look/feel" designers are more of graphic artists then UX/UI people. A good team should be composed of people from each of the 3 elements you described.

No matter whom you decide to go with look at the portfolio first. I can't emphasize this enough. If you don't like what they've done before then chances are you won't like what they'll do for you. If you want a "cool flashy site" find a person that builds great "cool flashy sites". Don't go for the person that loves minimalism.

Whenever I build a UI team I look at the portfolio first. If I like what I see then I look at the credentials and where they've worked. Otherwise I pass.

Richesh, From reading your updates it sounds like you want a graphic designer and not a UI designer. If you have a structure and layout that you like and just need someone to make shiny buttons and give you a good color palette then a graphic designer is what you're looking for.