Crusader first thing I want to say is good luck with this problem. It sounds very similar to what I went through a couple of years ago. We played at a community park and I asked for more dirt to be brought in that was clean of rock (or very little of it). I was promised and had people swear there was very little, if any, rock in the dirt. We got it spread and spent the next two years picking rocks out of the dirt. We would spend practices walking the IF with buckets and picking rocks. I even said that would be counted as conditioning on some days to help liven the mood for picking rocks.....again. It was so bad I hardly played any home games because it was so dangerous.
Ok none of that helped you but wanted to tell you so you know I understand exactly where you are coming from. Here is how I handled it.
First I got the county to buy this special drag which was designed to pick up rocks, cut and level the field and spread small mounds of dirt. It was a great tool and actually worked but the amount of rock was too great for this drag to make any difference. It was too heavy to pull with a riding lawn mower so we had to borrow 4 wheelers to use it. It's a great drag but it was expensive - a little over $1000. The expense is why we didn't buy it because we couldn't afford it.
What we finally ended up doing was going to the new county judge (who had a son on the team) and asked him if we could redo the infield. He agreed and used some equipment to come in and scrape about 3 - 4 inches of dirt up to get all the rock out. Then we came back in with clean dirt (Me and my pitching coach personally went out and found it) and spread it. That solved the problem.
You might be able to get the big equipment donated from companies if you ask - or at a discounted price. They like the good publicity that comes with doing things like that. Just tell them you will recognize them during games or in a program or whatever.
When it comes to rock it's a lot of work but it can be done. Good luck and if you need anymore info feel free to ask.
