I would suggest processing them to extract the pulp. I have a cheap, $20 foley food mill and that does the job for small batches. 30 lbs might be pushing your patience with that, but it can be done. Then you're going to want to freeze the pulp and hold onto it for some time. Typically lambics take about 12-24 months to reach maturity, and you're only going to want it on the persimmons for the last 2-4 months.
Lambic recipes are pretty much all the same: ~70/30 pilsner and wheat. Hops should be almost nonexistent. Use enough low A.A. hops as you can to get to 6-10 IBU. As for the fine details about the fermentation process, you are best off asking someone else. But this should be enough to get you off the ground.
FWIW, I made an amber ale with brett that I aged on persimmon pulp and it'd plenty tasty. When you age the beer on the persimmons it's going to make racking to the bottling bucket a chore and you'll end up leaving a good deal of beer behind, but for me it's worth the effort.
