Actually, it's pretty darn easy.
Casting boolits for your particular guns is prolly the most satisfying aspect of home made ammo. I can take a bunch of useless, dirty, greasy wheel weights and smelt them down and produce shiny, clean ingots of boolit alloy. Then I take those ingots, melt them down and cast some raw boolits. Then I customize those raw boolits for each particular gun I plan on shooting them in by size and lubing. Can't buy that feeling of accomplishment.
Get a Lyman 3rd or 4th Edition Cast Bullet Handbook and read it. Start out simple, don't overthink the process (yes, it is safe), and you can be casting custom bullets in no time (I started with a single burner Coleman stove, a stainless steel pot, a slotted spoon, a Lee ladle, a Lee mold, and a bunch of wheel weights I collected at work. I used alox for lube then grew into pan lubing. Controlling melt temp was the hardest part, but I made thousands of shootable boolits with that set-up). Lead is getting harder to find now, but still plenty out there if you look for it...
You can find hundreds of years of experience on all aspects of cast lead boolits here:
http://castboolits.gunloads.com/index.php