Crop Swap in San Francisco Bay Area

We have some lemons and plums in our yard, and I am thinking of joining a "crop swap."  My friend told me about it on our recent trip to Twain Harte, and I am going to research it.  We have so many plums and lemons that simply fall on the ground, then we have to clean them up.  This year I am making a resolution to use them or give them away.  The "crop swap" may be a perfect solution.