On The B777 on the FIX pages in the FMC I just enter range rings that correspond to the data supplied on our flight plans....and as if my magic they intercept our track, however ETOPS planning is just an excuse to get airborne, normally in flight any major emergency Fire/Failure etc. our QRH says.."Land at the nearest suitable airport"..this does not mean fly for another 3 hours to a planning airport if a suitable airport is closer, who knows it might nearly be below you!...North Pacific Operations can be a little tricky, I operated out to 207 minutes using say RJCC & PANC with a previous operator and sometimes nothing else was suitable.....