Hotels.com – Find hotels filtered by price/area/landmark/etc
Hostels.com – Find hostels arranged by country/city
Couchsurfing – I’ve had some great experiences with this community, both for places to crash or just to meet up for coffee etc.
Trusted Housesitters – House-sitting, accommodation for watching pets
World Nomads – Plot where you want to go, for how long etc, and they instantly give you a quote. Usually “Standard” or “Explorer”. Quite a bit cheaper than the Norwegian insurance companies I found and they will cover most of what you will need. You can also buy insurance from them during your trip (ie. even if you’ve already left your country of origin)
TripAdvisor – Travellers review/rate hotels/restaurants/activities