i use homestyler.com

many furniture stores have them as part of their website. Try Havertys furniture. Go to the bottom of the site. You can either put in their furniture or scale out drawings of other pieces etc.

What rawegg said... homestyler.com - I'm doing a whole new construction floor plan on there to give to our plan engineers to make right...lol. pretty good for a free online tool- lets you decorate, paint, choose floors, tiles etc. You can choose 'generic' furniture you can scale to your needs, or choose a vast number of products available in the catalog.