As mentioned above, I usually do sight reductions using the Nautical Almanac Sight Reduction (NASR) method. Sight reduction using HO249 was (is?) a more popular method than NASR and it is a straight-forward method; I prefer NASR because it requires the least volume of reference material – at the expense of more lookups and arithmetic. And the NA is available for free:

For a good time.... A digital watch works very well but needs to be occasionally calibrated using, for example, a radio tuned to WWW on the SSB (5, 10, 15 MHz). Frolic has an atomic clock that automatically links to WWW, something like this:

It takes about two weeks for the error in my $35 Timex wristwatch to grow from 0 to a few seconds. It’s nice to have several clocks aboard… (Darwin’s Beagle carried a dozen). Or read the time off your sat phone or GPS ;-)

Electronic aids. I’ve only seen dedicated navigation calculators in the class room and on ebay. Because my work often has me immersed in numerical analysis using excel, I’ve developed a few nav spreadsheets, and doing that really helps understanding - but there is some excel formula (trig/logicals) overhead involved so unless you’re already comfortable with that, I’m not sure it’s worth the effort. The best free software I’ve used is provided in USPS navigation classes, check out Celestial Tools and other stuff here: