It is only a three hours trip from Nogales. Thank you very much for your interest in our city, Hermosillo. Taking a train in Mexico, if any, seems not to be a good idea. Last train maybe was constructed in 1900. Additionally there is not such a passengers train service in Sonora.
Highway looks pretty much better and buses provide more comfort by far.
I do need an e-mail listing of people in Hermosillo. We thank you for your kind interest. Unfortunately, we can't provide any mail listing as requested. If you have a web site, we will be pleased to help you to make up your own list from people who visit you. Once available such a data base we can mail your messages.