If you're interested in Tunisian crochet, but you don't want to buy a special hook, I'm in the same boat. I love the Tunisian knit stitch, but I don't want to have a hook meant just for that.
But here's some good news: there's still some options for using a normal hook.
Option One: choose a skinny project. That's what I did for my headband. I was able to use a normal 5.5mm hook because the project was skinny and didn't require a bunch of working loops.
|This was made with the Tunisian Knit Stitch.
But, if you want to make a larger project, there's also option two!
Option Two: use a pencil eraser. That's right - a pencil eraser. You know the kind that fits on the end of a pencil? Simply slide it over the end of an appropriately-sized crochet hook and (hooray!) you've got a stopper on the end of your normal hook.
I've found that my Susan Bates 8mm (L-11) crochet hook works really well for this, but I'm sure there's other brands that work well, too.
After you've found the right hook, you have a lot more flexibility with your projects. That's because the working loops can push against the eraser, instead of falling off the end.
|See how much larger my project is than my hook?
That's because I have the eraser/stopper on the end.