I agree with above, ask for permission with a cute little kid along. If you don't have one or can't borrow one, the next best thing is swing by the local old farts home and grab one with a walker and offer him a buffet dinner for tagging along while you ask. Ask with the old fart crawling along and ask for permission for the old timer and you... it will work more often than not.

Other options,
[ul][*]ask to hunt coyotes or woodchuck's first. Once you have established yourself as trust worthy you can ask for more access.[*]Offer something in return. I once offered a summer beach hotel stay for a couple in exchange for being allowed to spend my vaca hunting on their property. They were so impressed they gave me access and never cared to use the vaca offer, which I would have gladly done.[*]Check out the property and look for something that needs help doing. When asking to offer help, be specific. I have seen most people aren't prepared with a chore for you to do, but if you see a fence that needs patching and offer to do that specifically people tend to weigh the worth of you doing that task with hunting access.[*]In Maryland in particular, make up some cards that offer for free to help in deer / landscape or garden conflicts and leave cards all over the local nursery's and garden supply stores.[/ul]
Those ideas ALL work, the toughest part for most people is just asking. Ask nicely enough times and you will quickly gain access to more land.