I've thought about doing metal detecting but like a lot of people I a not sure where I can hunt. We have a lot of stateparks that were Revolutionary War and Civil War sites but they do not allow metal detecting. :-(
I started out detecting in parks and then I realized the best targets are found on private property. Once you get into the hobby you need to bite the bullett and start knocking on doors and asking permission to detect. I only hunt parks now if I only have a small aount of time or I know it has the possiblities of still finding older coins.
If you look at the photo galleries on my site you can see the possibilities are there. All of my finds are within an hour of a large metropolitan city (most within 10 miles), and nearly all were found on public land. Some were even found within a few feet of modern shopping centers and office buildings!