Walmart, Home Depot, Lowes, and other major companies you can find on-line offer community grant opportunities that most schools would be eligible. You need to read the fine print. We are a private school and are not eligible for some of them.
There are also many foundations you can write letters requesting additional funding for a project. (Check your utilities)
Lastly, company-matching grants are wonderful. When a family donates, make sure you ask them if they have company matching grants and make sure you follow through to apply for them. Usually someone in HR is a good contact.

Might anyone have any leads on finding music and art grants? We are on our way to finally getting non profit status and would love to begin to take the opportunity to apply for applicable grants. Advice on the topic would be appreciated! Thanks.

I'd definitely check with the school district on its policy for grants. Even thought the PTO is independent, the grant efforts may be tied to the school. So, for instance, I know of a case where a PTO/campus successfully got a grant for a computer lab - but it covered only the computers. Unfortunately, they didn't consider the wider implications. They also needed furniture, networking, software, installation, and long term support by the school district, which didn't have the budget at the time to do all that.

There may be reporting requirements beyond what the PTO can handle. For instance if it's an educational grant, there may be followup reports on student success - information PTO won't have access to without the school's assistance.

So my advice is to coordinate your efforts with the school district. Surely some things truly are independent. But others may not be.

We have several parents who have expressed that their companies offer grants. My question is: does anyone have a committee that handles this part? It seems to me that we would have the parents get us the packet and we would fill it out and return. We live in a area with many large corporations that do community service projects. I guess where i am stuck is 1. do we send a letter out to all parents telling them if there company participates in grants we would love to have a oppurtunity to be a reciepent? 2. Does anyone else have this oppurtunity in their PTO and is there any problems that you have encountered. I am just not sure how to let the parents know that we want to be considered for there companies programs. Any help is greatly appreciated.