There are several methods that people use using putty or cork plugs, but I wanted something I could use straight away, without waiting for something to cure or dry.
The methods I came up with (i'm sure they've all been done before):
1. Drill a hole straight through and thread it with some twine and add a snap swivel. Knot it up and away you go.
2. Drill a hole straight through and thread it with a cable tie. You can either just cut the end off or add a snap swivel before cutting. You may have some slight difficulty in putting the cap back on the fishing pole with this method.
3. Add a plastic end cap that already has a hole in it. Push it on and you're ready to go.
I prefer number 3 as it is simple, clean and easy. And it looks nicer.