How do I find a good and trustworthy jeweler to make custom engagement/wedding rings for me?

Well it’s been 4 years and my girlfriend is getting impatient… Have been looking at some jewelry stores nearby, but, like most men in my position, I have no idea what I’m looking at.

I am a mechanical engineer by trade, so I am planning to design the ring per my girlfriend’s specifications using AutoCAD – I knew another engineer that did this and had a ring custom made, but I never got the name of the jeweler. I’m sure not everybody designs their own rings, but would a jeweler be able to work with my design?

Second piece of critical information: My mother is giving me the diamond from her ring, so I need to design around the stone. I assume I would just need to pay for the metal and the jewelcrafting. Are there other fees?

Finally, where do I find a jeweler that would properly treat the stone, without fear of stealing or damaging? I started checking Yelp, but I don’t know how much I can trust a couple of commenters on the internet. Of course that’s what I’m doing here on Fluther too! Thanks guys.