I'm a long-time Mac user and I recommend Pilotlog.co.uk
- it's internet-based so it also works on PDAs & (apparently) PCs.
Incidentally there's nothing (from the CAA point of view anyway) to stop you writing your own spreadsheet logbook, as long as you print it as you go. I did this for years but Pilotlog is much better, and keeps track of 28 day landing recencies.
They also do a 3 month free trial (for BALPA members anyway).