tour bus from shanghai or Suzhou to wuzhen. Where can I take t tour bus? Ned to purchase tickets in advance?

Well, you can take the tour bus from Shanghai to WZ at Shanghai Tourits Center General Station or Hongkou Center. I remember the direct bus leaves around 08:30 from the genral station and you can take it at Hongkou Center around 07:30. The bus will reture to Shanghai at 16:00 on the same day, so your round-trip ticket may have to be used in one day.

I heard the Tourists Center of Suzhou is at the local North Bus Station, where you may catch the tour bus to WZ. Don't worry! You can take a bus at WZ Bus Station to Shanghai directly.

From Shanghai to WZ CNY 128 per person (return tickets, admission, tourist guide service)
The admission cover the night time?

From WZ to Suzhou how much will it cost?
Any tour package as per WZ?

It does not includ the night time.
From WZ to SZ, the bus fare is around 105RMB.