I've had a bit of interest in Daito-ryu, since I used to study aikido. So, this topic prompted me to do a little web search.
It appears that there are a lot of Daito-ryu entities:
http://www.daito-ryu.org/
http://www.daito-ryu.com/
http://www.daitoryu-roppokai.org/history.htm
http://www.izzy.net/~dsharp/Yamabushi.htm
http://www.goshinkai.com/Pages/Main.htm
http://www.geocities.com/Tokyo/4856/
Then there's a whole list at
http://www.niagara.com/~zain/html/organize.htm
How can you tell which system is legitimately linked to Takeda Sokaku?