I really think an email address is all that is needed in this day and age.

You could put a tel no but obviously need to make sure it is always working...

I have read that one should avoid putting address on luggage tags as some say it informs thieves of a potentially vacant home.

The most important thing though is to make sure whatever is on your tag is legible. I used to work in lost luggage and it beggars belief how few people label their luggage. Of the few who do label their luggage in my experience in the region of 20-30% cannot write legibly!

It is also sensible to make sure your luggage is easily identifiable by avoiding standard black luggage, getting a bright coloured strap or two etc.

If your tag is legible and your bag is a bit unique it stands a much higher chance than most of being found and successfully returned...