Yup in Gt4 you can sort the cars in your garage by all types of stuff like FF/FR/MR/RR, brand, year, power, weight... you name it.
And yes the formula car/s is in the japanese row in Polyphony.
I now have 100% of the game complete and about 300 cars and there´s still a lot to go to have all cars available in the Arcade mode. Many of them can only be found in the used market and are really hard to catch. Looks like I've still got a lot of hours to really finish the game.... oh and you have to keep doing the endurance races in order to purchase all the racing cars you weren't offered ( the Le Mans prototypes specially since the cost 4,500,000 each!!, the best prize is 1,200,000 for a 24 hour race.... )