This sentence is in my coursebook: "Permette agli italiani di vivere una o due settimane a contatto con la natura e di riscoprire piaceri perduti della vita in campagna."
Is it the same as in contatto, because I can't find it in the dictionary? Is there a difference?
In this context no, I don't think there is any real difference. I find that I feel more comfortable using a contatto when referring to a physical contact (stiamo a contatto = we are touching) and in contatto when referring to a metaphorical one (stiamo in contatto = we hear from one another).
So a contatto con la natura conveys to me an idea of greater intimacy with Nature. But I have no official source for this, except my Tuscan origins :-)
You would use a if the "contact" is the means through which something works - e.g. lenti a contatto, azione a contatto, interruttore a contatto.
BTW -- I think it's a typo, but just in case, country is campagna, not campagma.
in contatto is used to describe relations between two or more human beings. a contatto is used to describe the relation with inanimate objects.
Edit: in contatto is used in friendly context, or in a direct relation between two people. It is often used in colloquial dialogues and involves direct talking. Ex: teniamoci in contatto, rimaniamo in contatto A contatto is referred to objects or to indefinite groups of people. It is often used to describe in a non direct way, the role of a relation between people. Then, using this expression, the relation is always indefinite and doesn't specify that talking is involved. Ex: "A contatto con il pubblico", "a contatto con il cliente"