I share your same concern. From my experience, increasing your view magnification to upwards of 400%, before selecting Find Font, makes it much easier to locate the blinking cursor.
Eugene's method works well too. However, for those who aren't paying attention, inadvertently pressing the wrong key command may change the text that that is being sought after. The risk is low, but it's still a risk. Of course, one could simply just press Command Z and undo the mistake, but like the OP said, if you can't find your selected text or blinking cursor in the first place, you may not realize you've even made a change to your text.