Buses leave frequently from the San Carlos De Bariloche Omnibus terminal, near the railway station, from 0800. The terminal is about 3km / 1.8 miles from the centre of town. Taxi to the terminal from the centre would cost AR$70 (Dec 2014). Alternatively, you could walk there from the centre in about 35 - 45 mins.
Ticket, costing AR$56 (Dec 2014) each way, could be bought at Viabaliroche counter on Mitre (street) in town or at the Omnibus terminal. The journey takes about 75 mins but remember, buses always run late here!
Keep in mind that at the bus station the bus does not have a specific gate, asking locals is best.
Buses leave for San Carlos De Bariloche from 0745 and the last one at 2200. See ‘Get In’ above for details.