Travel plans - where to start???

[Naguib]

I'm hoping to go to Japan soon, but I'm overwhelmed. I will to go through WWOOF- World Wide Opportunities on Organic farms - since I can stay with families for free. I have to organize with the hosts individually - and they're all over - so I don't even know which part of the country to choose. I basically just don't want to go where there's a difficult dialect. Can anyone recommend a source where I can just get a basic geography history overview besides wiki? I'm really lost.
Also, in terms of train tickets, is it a problem to book/buy them only a couple days in advance? I'd be hopping between families, and the plans will be made there, so I'm not buying them here (or will know when to buy them there) I also can't find prices for just a singular ticket - just tourist passes. I need to know how much money i've got to muster up.
A point in any direction would be nice - a personal recommendation, a site, a book?
Thanks!

[Belton]

What I found with dialects (Kyoto Nara Nagoya Kyuushu) was I couldn't really distinguish them anyhow, because my Japanese or my ear wasn't good enough. It was mostly just all foreign. Japanese however can switch dialects fairly easily and will usually speak the standard dialect with you. If you are going to spend a long time in an area, learning the dialect would certainly be a good idea in order to fit in a bit more.

Train tickets. You can buy them anytime up to the train arriving at the station. In my experience they are usually for a particular train rather than a particular journey. It is possible to change tickets but I've never had to so I don't know how complex this gets. At busy times getting a seat reservation might be an issue but there are always unreserved cars.
Although the rail network is extensive you might find you need to use buses in more rural areas.
This site has timetables and fares. The fares are pretty much fixed based on distance, with various supplements depending on whether you use an express, shinkansen, have reserved seating, first class (green car) etc.
http://www.hyperdia.com/
Also in the Kansai region there are two train companies. I don't know but you may find private rail companies elsewhere in Japan.
Depending on how much travelling you intend to do and how long you intend to stay a rail pass, or a couple of them *might* still work out cheaper than individual tickets.

For a very general overview of Japan you could try this site
http://www.japan-guide.com/e/e623.html