Visit www.HGTV.com. They really have a lot of good and clever ideas for holiday home decorations. They can also provide you with some fun ideas for making decorations for halloween as well.
Spirit Halloween, Party City are common nationwide stores that carry Halloween decorations. You can also check out home decor stores such as Home Goods.
Target or Walmart usually have a great assortment of decorations for Halloween. You can get tombstones made from plastic or styrofoam to plant in the yard. There are battery powered hands to put in the candy bowl and a wide variety of decorations such as spider webs and spooky signs and window decorations to make it a great Halloween at your home.
Halloween decorations for your christmas tree could be as simple as popcorn balls, some fake webbing, and candy corn decorations. Filling gloves with popcorn is also a good idea.
Spiders are great prop decorations. WalMart is a store that sells many items online. You can purchase spiders from WalMart and they will have it delivered to the store for free or to your home for a nominal cost.
There are some really great crafts you can make for Halloween decorations. I personally like finding old books at garage sales and burning new titles on the covers like "Book of Spells."
Making your own Halloween decorations can be a lot of fun and it doesn't have to be expensive. Some great places to get ideas are http://iblue.hubpages.com/hub/Top-10-Halloween-Homemade-Decorations, http://familyfun.go.com/halloween/halloween-crafts/, and http://www.squidoo.com/halloween-homemade-decorations.
Halloween or All Hallows Eve is a celebration done on October 31. Most Halloween traditions are based on folklore, and some some of the decorations used are from this such as the jack-o-lantern. Some other common Halloween decorations used are, witches, spiders, pumpkins, hay, and skeletons.
A good place to try trading some of your Christmas decorations for Halloween decorations would be Craigs List. You may also want to consider donating them to a store like Savers. They will give you a store credit that you can then use to purchase Christmas decorations.
Crafty halloween decorations are really fun to make with your kids. Try making popcorn hands or popcorn balls. Anything edible always seems to be a kid favorite.
Spooky halloween decorations would include things such as ghosts and ghouls. Try party city or your local party store to find spooky halloween decorations.
Decorating for Halloween can be a lot of fun, but it doesn't have to be expensive. Some great places to look for discount Halloween decorations are partycheap.com, halloweenmart.com, and orientaltrading.com.