Map of the Campus. You can download the full map as PDF file from KI.
Accommodation info (Note: this is not an endorsement of any facility):
The area closest to Novum, where you can find accommodation, is right in Flemingsberg, across the street from Novum and the hospital. The Attendo Park Hotell is located in convenient walking distance from Novum.
The next closest location to Novum is in Alvsjö, where Stockholmsmässan (Stockholm international fairs) is located. This is three stops away from Flemingsberg by pendeltåg. There are four hotels there:
It might be difficult to find rooms there during fairs, so you might try hotels or hostels in Stockholm in general, though closer to the main train station (Stockholm C), or Stockholms södra, would be more convenient for taking the commuter train.
During summer holidays (After midsummer to about middle/end of August), you will often find reduced hotel prices and good deals.
For finding hotels in the Stockholm area, you can use your favorite web sites.