First off, thanks for all the input and suggestions...
Our home is rather new and well insulated. It was one of the homes that was hit by the flood here in Alton when the dam broke in 1997 (?). We weren't the owners at the time. The place was gutted, redone, and an addition done. There's new windows, honeycomb-style shades, great insulation - our only gripe has been there's no storm doors, so we're putting those up this weekend. We've added on a sun room and it solar heats our downstairs alone on a good sunny day - even in the winter. It was about 75 degrees out there today!
Our furnace is less than 10 years old and we have it serviced each year, on schedule. We don't have a water heater but hot water on demand from the furnace. I'm not exactly sure how that works, to be honest. I know it's supposed to be an efficient way of heating the water we need for showers, dishes, etc.
Now, for what we're able to spend on secondary heating options... let me say that a huge project costing thousands of $$$ is out of the question. So, putting up a chimney or any major masonry work, etc. just isn't an option. Yeah, we could finance something but... that would depend on how it might help us in the big picture. My findings so far are that the device that makes the heat isn't the cost issue - getting it installed is the expensive part.
We've been keeping the heat at 60 degrees during the day, and 56 at night. We use electric blankets (except for the kids - but they're small and wear those fleece footie pajamas to bed.)
One thing I've found that I like the "plug and play" aspect of and it seems like the cost of running it won't be too bad, is a new Eden Pure heaters:
http://www.edenpurestore.com/
Anyone have any experience with these? We've got a small quartz heater we picked up at BJ's that we use in the sunroom when we're having supper out there or I place in the baby's room on super-cold nights. It's great and I never see an increase in our bills.
Maybe this is the answer?
(I don't mean to be a pest about this - neither hubby nor I are very handy and I grew up in apartments so this is new to me...)