How much almond flour/meal would equal 3/4 c. ground almonds?
That depends on how finely ground your meal is. Whether or not you can freely swap them out also depends on what recipe you're using it for. You'll only need a 1/2 cup of almonds to yield about 3/4 cup ground almonds (in your food processor), so I might recommend just going out to get them!
Ground almonds are typically not as fine as almond meal so I agree with Kenzi that you should be wary of making the switch. You can grind almonds in a spice/coffee grinder if that helps!
Also depends if almond flour is to be used as replacement of flour. Just measyre after grinding. Important, when grinding bleached whole almonds, add a teaspoon of starch or regular flour to catch the oil that otherwise you will loose on the side of the grinder. www.cooking-class-authentic-tuscany.com