I also have two children in school.More practically I have found the COIS London fairs to be the best place to find jobs, for me they have been the most successful. It is a bit of a meat market and, I feel you are on your own to make the best deal you can, but I have always found a job there.
Teaching in Europe will mostly poss a problem financially. I have seen few schools that offer housing, although this applies mostly to western Europe I have taught in Germany, Denmark and Turkey if you include them as Europe.
As stated before you are likely to be treated as a single. The school should definitely assist with how to obtain visas but may well require you to do the actual filling in of the forms etc and filing with the embassy. I have had to do this all three times.
The type of Visa you get is most important for your husband and unfortunately often depends on your nationality in many cases. If you have an EU passport you are laughing, but if not your spouse may or may not be legally entitled to work. It is important that you check this out when filling in your visa forms.
You may simply have to apply for a different visas or he may not be legally entitled to work no matter what. Then it is up to you to decide if this is a deal breaker or not.
If you are serious about working in Europe I would definitely encourage you to sign up for a fair, and as you are coming from Japan I would try to contact interested schools and set up some prospects before coming. Many of my European friends prefer the TES for finding jobs. TIE online is also good and gives a lot of financial information that I miss at COIS. I have also used Search and while I found the fairs themselves more enjoyable with fewer teachers and schools I also was unable to find employment, just could not find a good fit.
Also a few dollars getting access to their online lists can help you to get contact information even if you are not planning on attending the fair.
As you are a first timer I would recommend the larger fairs to give the greater chances of finding something.
Being bilingual is definitely an asset!
I can not stress enough the fact the money could be an issue, if you are living on one income then you are not going to be able to afford to do everything you want, or you wont be able to save anything or both. Europe is expensive and salaries are often quoted before taxes. Actually having a non teaching spouse can help with the taxes and you may well be entitled to a child allowance depending on where you go.
I think you will be able to find a job but make sure that you can live with the conditions of the offer. It is a shame if you are coming to Europe for the experience but spend all your time worried about paying the bills.
I know a couple who took a job in Spain for the experience, they were planning on supplementing their salaries so they could have the lifestyle they wanted. Not an option I would take but they knew it up front and had a wonderful two years.
Good luck on your hunt, keep your eyes open, make an informed decision and you should have a great time.