I've been heavily involved with nonprofit fund raising for years....so here are some ideas I have that could be relatively low in cost for your cause...
1) Consider a mail campaign - depending on how many mailing addresses you have, you never know how many people might respond to your cause and just write you a check! This works amazingly well for several organizations that are short on time AND resources.
2) Consider running an online auction - this is an AWESOME way to get to the people whose mailing addresses you don't have (ie you've got their EMAILS)...your email base can feel like they're using their expendable income on great stuff AND its going to their community at the same time!
I've included a link of one of the online auction companies that I've worked with...cMarket. They also have another website, BiddingforGood.com, that opens your auction up to all their members so that people who you don't even know can donate to your cause and bid on your items!
3) Instead of having a garage sale at your home, try having a "garage" sale on eBay! Think of it as a virtual way to get rid of some stuff AND make a little more money...(make sure you include the cost of shipping those items online or else you'll end up losing money!).
4) Have a fundraising event - give people in your community something to look forward to, and host a gala....you can sell tickets, have an auction, raffle prizes, etc that will give your community something to look forward to AND a perfect opportunity to donate to something they care about.
5) One last tid bit - consider selling sponsorships for your event...this can help off set some of your cost INCREDIBLY. You'd be surprised how many local businesses want to be a part of your cause-minded event! You can ask for anywhere around $500 per sponsor, and if you put your auction online, you can ask for even more than that because they'll be getting just that much more exposure through your website and event emails!
Best of luck with all of this! :)