Don Henley has set up a contest through Prizeo to benefit the Walden Woods Project.
There are several "tiers" which offer different benefits, depending on the size of the donation. However, no matter what the size of the donation, you get at least one entry into the contest to win two tickets to a concert and a meet'n'greet with Don.
In addition to the contest, there are other items you can purchase with the proceeds going to the Walden Woods Project. These start at $25 for a thank-you ecard from Don and go up to $25,000 for a walk around Walden Pond with Don! There are several price levels in between, including autographed items and memorabilia.
More information is on the Contest Page