I know this is an older thread, but didn't know if you guys still come on here, so I thought I would post to it. It really depends on what you want to find. If you are a coinshooter, I would recommend schools and sports fields. Most of the time, these won't produce coins of the older variety, but you can find jewelry if you are disciplined enough to dig your fair share of trash. If you want to find older coins, look for older houses in your area. A good tip is to look for houses that have more than one chimney, and ask for permission. Houses with 2 chimneys were built way back when. River banks can be good if they aren't loaded with trash. Try to concentrate on walking paths that have been used for a long time.
There are numerous places to hunt, just a little research needs to be done before you go. The more research, the better the find usually.
I wish you guys the best of luck. HH.