Beersmith rocks. Take some time to play with it. You will see that you can enter the temp of your equipment and ingredients and also the type.
Set the temp of the grain to 70 (or whatever you ambient temp is) and the temp of your cooler to what it is (I highly suggest you pour in a gallon or two of very hot water and splash it around and let it sit for a bit. This preheating will help limit the amount of temp drop you get when you add the grains) Set the temp of the cooler to the temp your preheat water is just before you pour it out.
Once beersmith knows the quantity and temps of this stuff, it can tell you to a degree what your mashing temp will be. I literally hit the exact temp I was shooting for (it turned out to be too high for my first batch, but at least I hit it exactly!)
There are settings for size and shape/type of cooler IIRC and everything.
It will also tell you how long to mash for. Not sparging enough will result in a lack of efficiency, and a smaller volume in the kettle. Beersmith will literally tell you everything you need to know, you just have to figure out how to read it.
Day after day, it reappears. Night after night my heartbeat shows the fear. Ghosts appear and fade away. Come back another day.