If you found that real estate agents are not showing your house enough or not getting offers, there is a very strong chance that your house is just not priced right. Before you determine what your home's Market Value is, it is important that you realize what it is not.
Don't be misled by insurance value, or what you heard your neighbor's house sold for. Don't be swayed by the investment you have in it financially or in memories and treasures. Instead, the true Market Value of your house is exactly what a buyer is willing to pay you. That number is based on today's market, the economic conditions, your competition and relative merits of your home, property, and of course location, location!
The only way you can judge that you priced it right is by how fast an offer comes in, period. If you price your house right, buyers, who have seen a lot of homes in person and on the Internet, are just waiting to swoop up a house priced well. And, the realtors will see this themselves and call each and every buyer in your price point that they are working with, knowing that a house is priced well and eager to show a buyer as soon as possible.
When a house is priced right, buyers are less likely to make low ball offers for fear of losing out to another buyer even in this market. However, if your home is overpriced during the first few weeks, when the most buyers will visit, they wont make an offer at all. Therefore, after 3 weeks, you should reduce to the next 'level' to get those buyers back for a second look and new buyers as well.