Here, people bag leaves for trash. If I see a big haul, 7 or 8 bags, I have rang the homeowner's doorbell and politely asked if I could have them. I've always gotten an OK, and one person called me for years after that (I left my phone #) to let me know when he was going to dispose of leaves because he always had a lot.

Try posting your wishes on freecycle.org Ask for leaves, straw, grass clippings, paper shreds, spoiled hay, rabbit or guinea pig bedding, etc Sometimes people have a one-time deal, such as leftover clean bedding from a now-deceased pet, but if you are lucky, you may be able to find someone who can give you a steady supply.

I found three guys raking leaves at a small office complex last fall and asked them to dump their truck-full of leaves on my driveway. They did, twice, and now I don't have anyplace to park my car and haven't been able to use the garage all winter!

The other good source for mulch (wood chips) is a tree trimming/killing service.

I rarely find free straw but every now and then a bale turns up mixed in with the hay bales and I get that. Hay also works, but around here, it's dearer than oil.