It is better to start looking for homes offered for swap online. There are many specialized websites, where you can look for offers for home-swap. Or else, search the websites of real estate agencies that offer this service. You can also use different social networking website to get some information about the process.
Look in the newspapers. Sometimes, newspapers carry advertisements of families who are looking for home-swap and you can find the one that is within your specified terms area. Searching your local newspapers, especially those with free circulation option, can have such an advertisement and you might be able to find someone within your community who wants to swap a house at the place where you want it.
You can also post your own advertisement at a website or even on social networks to let people know that you are interested in swapping your home at a nice place. It is possible that someone is as interested in home swapping as you are but does not how to find it. There are many groups or people who are interested to swap homes for holidays or some other reasons, and you can find a nice place to live for yourself.
If no other option works for you, you can seek help from a real estate agency that offers help in the area of home-swap. It can be in the same area or anywhere in your country, because generally these agencies are in contacts with tourist organizations or real estate agencies in other parts of country and can get you in contact with another person in another part of the country where you can swap your home. Their level of market search and information is better than you and you can let them handle the matter professionally. Make sure you know if it is a viable option for you.