There are hundreds of great options for places to stay in Bariloche; you can start looking with the search box!
If you are a backpacker and are looking for affordable accommodation & want to meet other travellers, then your best option is somewhere is downtown Bariloche. This is where most of the hostels are and you have access to transport links, restaurant and bars all within walking distance. My personal recommendation for a great hostel is Perikos Hostel, it's a quiet hostel with small garden, communal kitchen and all the facilities you would expect. You will be able to book all your tours and activities through the reception. If you are after a bit more of a party hostel try the established hostels on Salta streets such as Marco Polo & Tango Inn.
If you are going to hire a car, then parking in the downtown Bariloche isn't the easiest. With the flexibility that a car brings, I would suggest heading out along the 'KM's'; this is the main road 'Av. Bustillo' that heads west towards Llao Llao, Circuito Chico & the National Park. A great up-market hotel option with lake views is the Lirolay Suites, 7km's from the downtown Bariloche. The El Casco Art Hotel is right on the lake shore & if money is no object then try the famous Llao Llao hotel.