I have been interested in the same thing in Southern Oregon

Good as place as any I guess. Probably would have been better in GPAA Claims section but this will work. I'll start out with the lease. Finding an owner with property for lease can be a challenge even more so a property with viable gold that is not going to cost you the lions share of the returns.
to find a spot that you might be able to make a deal with an owner I would suggest that you follow the old adage that the best place to find gold is where gold has been found. Look at the more popular mining districts in an area that you are interested in working then use the LR2000 and the new MLRS (January 2021 launch) to find the claim names and then the Serial Register pages to find the owners info. From there you will go old school and send them a letter to see if they are interested in working with you. I have been known to send out a lot of letters asking owners if there is an interest with all of my contact information and then the waiting game starts.
Other than that I would suggest and this is my favorite, find a claim. using the first part go to where gold is and start prospecting then prospect some more. It will be a lot less money in the long run and you will have the satisfaction of knowing that you did it all.

I'll add to Kevin's information. Depending on the state, and management agency, anything more than hand tools, and that could mean your trailer mount plant, could require a Notice of Intent (NOI) or Plan of Operation (POO), along with a reclaimation bond. Getting those through an agency and final approval can take considerable time, depending on where you're at.