Anyone can recommend 3 star hotel in Shibuya for 3 persons? Well, here I am not answering directly to your request, but I guess you unfortunately have a narrow range of choices among hotels (in urbanized areas in Tokyo) which offer any room for three or more guests.
Assuming you are three travelers, I suppose
: If you dare need to stay in one hotel room (for example because a little kid is among you), it could be difficult to find one which is good also in other terms such as location and cost.
: If you can stay in two hotel rooms, you would have a better choice, because hotel rooms for one or two guests are more common.
When you choose one among hotels in Shibuya, I recommend you pay attention, not relying on old sources, also to routes or distances from/to Shibuya Station(s) to/from hotels and from/to hotels to/from your destinations.
Shibuya Station buildings and districts around them have been on some redevelopment projects.
The Shibuya Station complex consists of a few buildings, with railroad tracks lying from the 5th basement to the 3rd floor above the ground.
Shibuya has many slopes, and some entrances and exits of Shibuya Station buildings are around the bottom of one or plural slopes.
Regarding hotel ranking, I am not sure which ranking you are looking at.
A few things about hotel rankings in Japan which I can think of are
: A higher-class hotel is not always ranked higher.
: Even a higher-class hotel or a higher-ranked hotel may not have enough attendants who can speak English well.
: Persons who rank hotels may vary by rankings, for example, only a low percent of guests in one ranking, while investigative members of a certain tourism company in another ranking.
Personally I seldom care much for how hotels in Japan are ranked when I choose one, not only because I roughly evaluate them based on information which they provide in my language Japanese, but also because I take hotel rankings as not highly reliable if I cannot presume who are ranking the hotels by which criteria.
[Examples of results of searching for hotels]
Results mentioned below are concerning one night from 22 October 2014, which will be not a public holiday but a normal weekday in Japan.
Hotel charges may be indicated in the total, in the amount per room or in the amount per person.
(A1) Three adults (from 13) in one room:
http://www.jalan.net/en/japan_hotels_ryokan/Hotels/Tokyo_Hotels/Shibuy...(A2) Three adults (from 13) in two rooms:
http://www.jalan.net/en/japan_hotels_ryokan/Hotels/Tokyo_Hotels/Shibuy...(B1) Three adults (from 13) in one room:
http://www.japanican.com/en/hotel/list/13/130206/?so=c&navcheckin=2014...(B2) Three adults (from 13) in two rooms:
http://www.japanican.com/en/hotel/list/13/130206/?so=c&navcheckin=2014...
