Tateyama route

when the new shinkansen opens in Mar 2015, would we be able to get a direct train from Tokyo to Tateyama to see tte Alpine route. and how long will it take from Tokyo to reach that place. Would we need to reserve in advance for the train.
Please help.

As far as I know that answer is no, the shinkansen does not stop at Tateyama. You would need to change at Toyama and take the Toyama Chiho Railway.
Here is some information to have a look at:

The article about the new shinkansen extension showing the route
http://www.japan-guide.com/news/0033.html

The access to the Tateyama Alpine Route page showing how to get around (and roughly where some of the new stations for the shinkansen will be)

The shinkansen timetable (from page 12)
http://www.jreast.co.jp/press/2014/20141222.pdf

Seems as though it takes around 2 or 3 hours from Tokyo to Toyama depending on which kind of shinkansen you get, plus an hour to the Tateyama Alpine Route form Toyama.

Oops forgot the link to the access for the Alpine Route page
http://www.japan-guide.com/e/e7551.html