There are a lot of questions that have been posted a lot, but if you haven't found what you need to know, there is no harm in asking again.
Contact printing is the most basic print making method, but, at the same time there are a lot of dimensions. For example, are you looking for making proofs, or making prints that are intended to stand on their own? Even though both are done by contact printing, the equipment approaches are different.
So, what is it you'd like to know?