Mold tool integration

Id like some simple advice on mold design with regards to the integration with the mold machinery, the impression designs themselves are very simple and as i have a high speed VMC i want to make them myself, which isnt a problem, where im a bit lost is how i design the back side of the mold tool. What is the standard procedure, do molding companies provide design documents detailing the positioning and type of connections required? I was hoping for some help on the standard approach to this before i contact molding companies as I cant imagine they want to completely baby someone through the process and would prefer to work with mold tool manufacturers rather than people making their own molds.

Our main products are plastic mouldings but as they are very small medical components we outsource all the mold design and manufacture so i have very little experience in the actual mold design, although i've lots of experience in designing products to be molded.

Thanks for any help.

SolidworksPlastics And Mold Design