The house I own had no heating system other than a blower box on the fireplace when I bought it. Several thousand dollars later I had central heat with a heat pump in place. I thought all would be great, until I got my first heating bill. If I use that thing I can expect heating bills to range from $300-600 a month in the winter.
SOOOoo I have become something of an obsessive about tricks and alternative heating sources.
1. You would not believe how much outside air leaks into your house. Go around when it's cold and windy and put your hand over door cracks, keyholes in the knobs, window sills, even along the floor by the wall. If you can't plaster over the leak, tape it. All that cold air coming in just drives up your costs.
2. A $4 flannel blanket from Walmart works wonders when hung over doorways that are not regularly used. I also hang them over windows as a cheap alternative to heavy drapery.
3. Those fireplaces? Forget 'em. They'll suck out more heat than they put in. The only time a fireplace really does good is if you are either right in front of it, or you have a blower insert that forces the heat out into the house instead of sending it all up the chimney.
4. I can't say enough about those $1.25 draft dodgers that you stick on the base of your doors. Just peel the backing and stick them on. Any hardware store or Walmart will have them.
5. Insulation. When is the last time you checked it in your attic? You lose a LOT of heat through the ceiling, so a few hundred bucks worth of blown in insulation can save you thousands over a few years. You need at least 6 inches of insulation up there (I put in a foot!), so if it's all compressed down to a few inches, it's time to resupply.
Look around, you'll find one of those radiators. I finally realized the heat pump was very efficient until the outside temp dropped below 45, then the meter nearly spun off it's base. So, I hooked up a free standing, vent free, propane fueled fireplace that will make the place toasty warm when the temp drops into the 30s or below.
Avoid the temptation to get little electric space heaters. The energy they use up to make that little bit of heat is NOT worth it.