Answer 1 Ebay! Go to the “clothing” category, narrow your search to “Tops” and use the search for keyword “rhinestone”. You’ll be surprised at how much is available.
Answer 2 You can go to any clothing store.But if truth be told rhinestone anything is a big no-no they look fake and tacky like your trying to be cool.Trust me steer clear of rhinestones.If its fake you dont wear it blazened on your chest.
You could try doing it yourself buy buying beads online and sewing or glueing them onto clothes – Swarovski crystal beads work well for this.