By Plane -- Air service into Futaleufú has been shaky since the Chaitén eruption, though you can try Aerotaxis del Sur (tel. 65/252523 in Puerto Montt, or 65/731268 in Futaleufú; www.aerotaxisdelsur.cl) for charter flights from Puerto Montt, weather permitting. It's entirely feasible to fly into Esquel in Argentina from Buenos Aires and then travel by road 65km (40 miles) to Futaleufú; just be sure to factor in a possible delay at the border crossing and plenty of time to make the 3- to 4-hour journey.
By Bus -- During the summer, bus service with Chaitur (tel. 65/731429; firstname.lastname@example.org) used to leave every afternoon at 3pm for the 4-hour journey ($10/£6.70); however, timetables have been affected by the eruption and you should now definitely check ahead for updated information. The same goes for Turismo Pineda (tel. 65/731298), which typically runs a service from Chaitén to Futaleufú on Mondays, departing at 12:30pm, for $10 (£6.70). Winter service is sketchy; try calling B&V Tours in Chaitén to see if they have an upcoming trip (tel. 65/731390). From Puerto Montt via Argentina, Turismo Futaleufú (tel. 65/721215) has a Tuesday trip for $42 (£28), returning Thursdays.
By Car -- From Chaitén, take Rte. 7 south and go left to Rte. 235 at Villa Santa Lucía. The road winds around the shore of Lago Yelcho until Puerto Ramírez, where you head northeast on Rte. 231 until you reach Futaleufú.