if you're in a rural area, chopped pine needles (balsam pine is best) make a nice sachet all by themselves.

orange peel can be dried (it can be diced, sliced and dried around toothpicks to make spirals or corkscrews, or left natural) Lemon and lime also works this way
lavander is a classic and always sells well, in blends or by itself...

you'll nice I have a thang for single-note or very simple scents...but I'd rather be able to market something as 'natural', and I'd rather put two sachets in a drawer than have one muddy scented bag of stuff.

whole cloves show up in the dollar store, or in BIG containers at some food store- and they're totally useful for everything, and have a rich 'harvest' smell.

cedar shavings aren't pretty, but you can put them in a muslim bag, and dress it up, and they're great for the sweater drawers. they come in big bags from the pet stores.