Tokyo ferry terminal directions.

On arrival at Tokyo we will need to travel to the ferry terminal for the Tokyu Ocean ferry to Tokushima. Address is given as 4-15 Ariake, Chuo City.Is this near Odaiba? What are the alternatives to get there from Asakusa please? How long should we allow - check in is 1800.

Yes, it is close to Odaiba:
http://www.otf.jp/tokyo/

Okay,good,close to Obaida,mmmm.
Anyone know how to actually get to the ferry terminal from Asakusa?
Seem to be some rail stations nearby and maybe a boat landing for a Sumida ferry......

From Asakusa Tobu Station take the Tokyo Metro Ginza Line or Toei Asakusa Line to Shimbashi Station. From there take the Yurikamome Line to Ariake-Tennis-no-Mori (aka, Ariake) Station. Fare is 560 to 580 yen total and takes about 52 minutes on the Ginza Line and 47 minutes on the Asakusa Line.

Exit west side of Ariake Station and head southwest and in a short distance there is a traffic circle of sorts with many buses. According to the website Uji provided above, there is a shuttle to the ferry port with a cost of 200 yen per person.

I would take either the 16:26 Ginza train or the 16:31 Asakusa train. This will get you to Ariake Station by 17:18. There is a shuttle departing at 17:30 and 17:50 to the port (according to the webpage). The earliest shuttle departure is 17:10. Travel time to the port is about 10 minutes.

The ferry option can be researched at this website:

http://www.suijobus.co.jp/price/index.html

It looks as though you would take the ferry to Hinode Pier and then transfer to the ferry to Tokyo Big Sight.

Asakusa to Hinode Pier takes about 40 minutes and costs 760 yen. Hinode Pier to Tokyo Big Site takes about 35 minutes and costs 400 yen. You will still need to take a taxi or bus as it is a two kilometer walk to the ferry terminal/port.

Thanks so much Paul - that's great!

Is there also a way to get to Ariake Station from Asakusa that includes going over the Rainbow bridge? That looks exciting!

Yes! Take the Asakusa or Ginza Subway Line from Asakusa to Shimbashi and transfer to the Yurikamome, which goes over the Rainbow Bridge:
http://www.japan-guide.com/e/e3008.html