This is so funny. Just yesterday we had my wife's parents over for a fence painting "party" and served iced mocha coffee with lunch. Very nice pick-me-up on a warm day.
Here is a link to a recipe I've used a few times. I think it's pretty good, although I cut back the sugar to 2 tablespoons and skip the whipped cream. You can also adjust the amount of chocolate syrup to your own taste.
How to make homemade Frappuccinos
Oh, and to save time, I make the coffee up ahead of time and store it in the fridge. It actually works better this way because it's already chilled and doesn't melt the ice.