Steve,
If you go to that auction site e*** and search for arrow saws you will see the American Archery cutoff saw with the in line on/off switch for $65 or a similar Weston for the same price. Of course there is shipping too. The Apple saw is $125 with the switch and is heavier duty. The less expensive models will work well, they just are not as robust and will not hold up as long. I have an Apple, but it is twice the price and you really don't need it if you don't cut a lot of shafts. A Dremel tool with the other supplies you need will cost as much as one of the less expensive arrows saws. On the other hand, you probably already have a Dremel, so if you want to try to use it, here is the advice I got from JC (Joe Coots) on the easiest and one of the best ways to use it.
Put one of the abrasive cutting discs on the Dremel. Mark the arrow all the way around at the exact length you want to cut it. Get the Dremel spinning and cut off the arrow at an angle about a half inch longer than the mark (this will give you room to cut parallel without having the extra length of the arrow shaft hitting the Dremel tool). Next, hold the Dremel tool so that the cutting edge of the disc is making a perpendicular cut in the shaft just a little longer than your mark on the shaft. Then hold the Dremel tool so it is pointed straight up with the disc on top like a little umbrella. Spin up the disc and hold the shaft straight above the Dremel tool with the cut edge of the shaft pointed straight down -- and bump the shaft lightly against the flat surface of the top of the disc to grind the end of the shaft to the line you made for length keeping the end of the shaft square. To really square the shaft, a G5 ASD can be used after the process with the Dremel. Unfortunately, the cheapest I have found a new G5 ASD is $32, so the inexpensive arrow saw starts looking very reasonable compared to buying the ASD. I will admit that I have the ASD too and it works very well for squaring up the ends of arrows as well as squaring the fronts of inserts. One nice thing about the Dremel tool and ASD is that they take up very little space and can be taken with you in your vehicle on hunting trips if you want to build arrows in the motel or even in your vehicle using a 110v inverter for the Dremel. You don't need the ASD if you are good at bumping the shaft with the Dremel to grind and square the cut end. You could even use that technique with shafts you cut with the Harbor Freight chop saw. Or you could buy the ASD and square arrows cut using the chop saw.
I don't know if any of this helps, but I'm trying. I'm sure others have all sorts of devices they have built that work well.
Allan