Fizzy Fish

Personally I wouldn't bother with the tracker - they're expensive, plus I know a number of people who have had them but haven't got their bikes back after they were taken. Better to spend the money on security to stop the bike getting nicked in the first place.

Chaining the bike to something solid is a good start, plus get a cover on it as well and try and keep it hidden if possible (e.g. round the back/side of house rather than in front). If you have two ground anchors, use one for the frame and one for the wheel - really the more awkward it looks to take the better!

The other thing that can be helpful if you have the space and are really concerned about the area, is one of those metal bike sheds, though they are expensive.

I always have alarms on my bikes, but there's divided opinion on how effective they are given the money. Probably better to spend your money on the above instead.