What Super said. As for brand though I would recommend Gold Tip arrows. You can buy more expensive ones but the GTs are hard to beat. The GT chart calls for a 500 spine arrow in the 45-49# draw weight range and 26"-29" total arrow length. If to be used for hunting however, I like to go up one spine stiffer - in your case a 400 spine. For strictly target shooting the 500 spine should suffice.
And if you fletch your own arrows, you can get cosmetic blems on Ebay for a real good price.