I am going to tell you how I got donations for my auction. What I am going to tell you is going to be a lot of work, but work is what it takes to get donations. This was my first year as auction chair, and our final total ended up being 150% higher than last year. I spent every free second of more than month gathering email addresses of local businesses. I sent them a nice email with my donation letter attached. None of this is a guarantee. Some say yes, others no, even more don't bother to reply. But the more people you contact, the more chance you have of getting donations.
The way I see it is if someone is advertising their business, they are looking for new customers. A donation could be a way for them to bring in new business, if they see it that way, so why not contact them? All of that junk mail you get in the way of postcards and brochures? Look up their business and email address. The valpak or money mailer coupons you get? More businesses to contact. In the car and see a billboard or poster stuck in the ground? Pass an interesting business? More names for you.
What I do is use my best friend google to see if the business has a website (not all do). If there is a "contact us" link, there should be an email address there. If they only have a form to fill out, I fill it out and ask a question like "are you open on Sundays" or "do you accept competitor's coupons?" When they reply to you ... bam, you have their email address. If there is a facebook page, if their address is listed on the left side, click on it, and if they have an email address, it should be right there.
Again using google, I type in my town name and an activity (ie martial arts Raritan). If it is something that isn't as common in town, I use my county (ie golf course Fairfield County). What you end up with is a list of businesses with links to their webpages, where you can look for more email addresses. Examples of what I try to find is: gym, health club, spa, massage, hair salon, nail salon, waxing, tanning, chiropractor, acupuncture, lawyer, billiards, boxing, golf, mini golf, roller skating, ice skating, trampoline/jump, birthday party, yoga, rock climbing, dance studio, petting zoo, pumpkin patch, corn maze, skiing, cupcake shop, bakery, pilates, car wash, ceramics ... and there are so many more.
Again, this is all very time consuming. I have received donations from 5-10 percent of these places. If you are lucky, you may get more. But for me it is easier than hitting the streets, I can work while laundry is in or kids are at activities. And now I have all of this information for next year. But all of this hard work, coupled with the wonderful information on this site, is what helped me and brought me to tears when I got our final total.