Depending on what kind of initiative--nonprofit design services, a single project, landscaping--what kind of project are you talking about? Look for CDBG - community development block grants - in your area. Look for community grants provided by relevant local corporations (or not local) looking to increase goodwill. Many corporations have foundations looking to give money away, think about what's in your area. You could talk to the local university extension agents or maybe chamber of commerce (these types usually know about grants beyond those that are strictly architectural). I attempted this in a small town, where I knew everyone, and I went straight to the local banker who was willing to put money up for something good for the town.

More broadly, research design collaboratives (there's one in Philadelphia, I believe) and call em up & ask where they got their money. Talk to non-profits that might spend 30% of their time just finding funding. Don't narrow your search to just "architectural grants"-- you can find ways to get a specific project eligible for many types of grants.

I'm curious what type of project you're doing?

I'm working on starting a community based-and-benefitting architecture and planning publication. Where most new mags that come out are strictly dedicated to high design, we would aim to make the design of the city more accessible to a wider audience. We know this will take time, but my city has no publication dedicated to this now. We would also provide a bridge between the many bickering organizations here and collaboration (we hope).