Create a furniture space plan that divides the large space into smaller more intimate spaces. Console tables, double-sided fireplaces (vented or ventless), and cabinetry are additions that can help transistion spaces within an open floor plan.

Use bookcases and folding floor screens as room breaks, like this

This is a quick and easy way to create division within a large space or even to create an entry where there is none. If you need a very private division use solid back bookshelves or upholstered room screens. Hope that helps. Let me know if you need further information. Charmean Neithart
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Double sided fireplaces look great, or maybe you could make a little liabry enclosure with bookcases. We are having the same trouble with our revenarated barn. We are putting in big shelves that create kind of rooms :)

The simplest way to delineate the various groupings in an open floor plan is with rugs. Curtains hung from ceiling tracks can be effective dividers that take up very little space.

After re-reading your post, I'm not sure we're answering the question - can you post pictures or a drawing of the space?

You can easily acheive this by creating groupings of furniture to define spaces. I like to use rugs to anchor the space, as well as play with the ceiling and lighting to help establish certain areas such as dinning spaces. I have attached a picture to help you understand better..

Area rugs, consoles, bookshelves and screens can all create a sense of separation. We are looking at a house where we may put up a floating wall with a niche to separate the dining from the family room. Storage closets will be on the perpendicular side of each end. One side will hold the dining buffet and the other a media center. You need an element to stop the eye.

Thanks for the advise! You've given me many ideas I believe I can incorporate into my house. It's great to have access to so many creative minds. I love this website!