Quality Hotel Nacka
Park Inn in Hammarby Sjöstad
Park Inn is fairly close to the convention. There are no special convention rates.
Gustaf af Klint is on a boat close to Slussen (The Lock) and 2 kronor and Archipelago in Gamla Stan (The Old Town) are situated near buses and the train Saltsjöbanan which rapidly can take you to the convention site. There are several more youth hostels to choose from.