The keys to keeping prices low is buying components in bulk, but you can really only do this once you have your pet load figured out. the second key is to start saving your brass NOW!!!. my cost figures do not account for brass, i started my brass for almost a year before i started reloading and did not figure those costs in. the only brass i had to by was .38spl and even then it was cheap.
in my experience, cabelas will run decent deals on primers and powder, but are expensive when it comes to bullets and the selection is pretty limited.
for primers & powderhttp://www.grafs.com/https://www.powdervalleyinc.com/
every once in a while, Midway will run a special with free hazmat shipping, which is also a good time to buy, their prices are usually pretty competitive.
im fortunate and have a really good shop an hour away that has really good prices and selections for powder.
i bounce around quite a bit and it depends on who has the best prices at the time i need them, but i always buy by the case to get the best price. http://xtremebullets.com/https://www.berrysmfg.com/http://www.bayoubullets.net/https://www.ibejiheads.com/
xtreme has a brass credit program that can help subsidize your bullet cost since freedom ammunition needs the brass. you can send it in and get roughly $2 a lb in credit. they take brass for anything they reload too. just no aluminum or steel cases.
with as much as you shoot, i would look at dillon products over a single stage setup. the square deal press will suit your needs well if your only looking to reload .45 colt. If you think you are going to really get into reloading and want to load several cals, i would look into a Dillon 650 or a hornady LNL-AP..
the first year i started reloading i sunk $800 into getting my hornady set up and recouped the cost in less than a year (4,000 rounds at $110/k compared to buying factory ammo at $220/k). as a note this does not include the cost of your time. but given your son is what in his late teens now, he could easily help out too.
truth be told, i dont really save any money shooting, i still spend the same amount each year but for the same money i get about twice the ammo because i reload.