looking to speak to a professional product vendor

I am wanting to find out the ins and outs of 3D vendoring generally and the general concepts of how products are made as I have developed a big interest in it. Are there any pro 3D vendors that generally frequently do give out this advice or information? I would assume it would be on a one to one basis with some sort of payment upfront or whatever (as long as the price is reasonable). If any venders here can help me with this request or anyone can point me in the direction of who to ask i'd be greatly appreciative. Ty.