The reason to get into reloading is because it will magnify your enjoyment of shooting. Your ammo will be more accurate. Each gun will have more flexibility (lite loads, stomper loads, light bullets, heavy bullets, fine tune for a particular application, etc.)
You can certainly save a lot of money if you don't wind up shooting twice as much.
Cost to get started? Well, do you want "Chevy" equipment or "Cadillac" equipment. A Lee Anniversary kit contains most of what you need, and it runs $70-$80 at
www.midwayua.com. There's your Chevy. An RCBS kit runs what, $350? There's your Cadillac kit. Or you can do what I did, and shop garage sales, and gun shows, and buy used gear cheap. I was under $60 invsted when I loaded my first shells. Got up to about $120 pretty quick (mostly because I bought a caliper at retail.)
Current costs for me:
9mm is $3.61 per 50, using Laser-Cast bullets. The bullet is the most expensive component.
.223's are running me $3.77 per 20, but that's because I'm buying good bullets at small quantity at retail. If I switched to cheap milsurp "pulldowns", I could almost cut that in half. But the load I'm using is awesomely accurate, so maybe I'll keep paying $3.77 per 20. (Because I get about 20 dead Prairie Dogs per batch...)
I don't do shotguns, yet. But my buddy tell me he's at about $2.50 per 25. That's buying components pretty smart.