Your desire to help and provide a better service for your community is to be applauded. The work of a public safety diver requires continuing education, a high degree of physical and medica fitness, and a commitment to perfection and you are willing to VOLUNTEER. Way to go!
Additionally, it takes a TEAM and with regrets, this is not something you are going to be able to take on by yourself. Conventional wisdom suggests a six man dive team consisting of a primary diver, a safety diver and a 90% diver. These three divers are supported by a team leader that is well versed in all aspects of public safety diving (with a focus on safety) and has considerable experience. The divers are also supported by a primary tender and a safety tender.
It might be advisable to contact the closest PSD team in your region and ask if you can participate as either a diver or surface support person. They could share a lot of their knowledge and I would bet that they would welcome a good guy with a great attitude.
One thing that you might consider is becoming familiar with SONAR. The downfall of drag hooks is you can disturb evidence, potentially move the body away from the "last seen point," trash any visibility for responding divers and there are other downfalls (but not enough room on the forum).
There are many SONAR systems available and if you could do a good search using technology, you would be much better off than trying to start a one man dive team with limited support. I am certain you know that public safety divers do die and it is not uncommon to loose 2 to 3 per year. The PSD community just had a double fatality in Mexico two weeks ago.
A good "start up" SONAR system is the Humminbird and information can be found online at:
Humminbird - Side Imaging Technology
I am certain other forum members might have other ideas too but whatever way you decide to go, I wish you the best.
Stay safe!
Blades Robinson