Watch to wear while running - gps/mileage/time?

Aperture_Science

Training for a 5k a standard digital watch with stopwatch function should be fine for the timing aspect.

To work out how far you've traveled:

low tech is a map and distance measuring device like this http://www.amazon.co.uk/Gelert-com70-Map-Measurer/dp/B0010E57MG/ref=sr_1_1?ie=UTF8&qid=1329322458&sr=8-1

High tech Map-my-Run web site.

By all means if you fancy a GPS watch then buy one, but you don't need one.