You might check in your yellow pages for someone running a small machine shop or welding operation. They might gave a bandsaw or big chop saw. Depending on how old your blades are they might be L-6. At one time all those blades were, but newer ones are out of a steel I can't recall at the moment. I've often wondered, casually, about lawnmower blades, but not being a forger I didn't persue the thought. Again, I've no idea what they're made from. Trouble with working with unknown steel, is you can sometimes have a rough time with the heat treat/temper cycle; although I guess heating to non-magnetic and then using a reasonable temperature for tempering works. I've made knives out of files whose steel I wasn't sure of that I ground cool and then re-tempered them at 400 F until I got the straw colour. That worked ok.