1. Heirloom Pumpkin Candle:
Large tin, small tin, and the diffuser (works just as well if you don't like candles).
2. Cinnamon Broom:
It's not really something I want displayed in my home, but I have found that hiding a cinnamon broom behind the sofa makes the entire house smell as if I'm baking up something delicious! You can find them at any market, but here is a link in case you can't find one and are interested.
A very inexpensive way to make your entire house smell like fall is pushing cloves into oranges and displaying for all to see (or you can hide them). You can find instructions on how to make them here.
Lastly, I'm not adding this to official list- but, my absolute favorite way to make the house smell fall like is whipping up a batch of apple cider (recipe below). It takes a few minutes to make, but your house will smell divine for hours ;)
1/4 cup of real maple syrup
1 orange peel
1 lemon peel
2 Cinnamon sticks
Juice goes into saucepan, add syrup, add the rest of the ingredients into a cheese cloth, and then simmer for at least 10 minutes without letting it boil.