Pop on in to any decent automotive supply store and check out their autobody section. You should find just what you need by way of chemical strippers. Or, failing that check into your local Home Depot and see what they have on the shelf.
Once you have the chemical of your choice, pour some into a glass container such as a caserole dish, (hint: for those members living with their parents or even a significat other please don't raid the cookware. Go down to the local thrift store and find one) allow the blades to soak for a reasonable amount of time. The chemical should have some instructions printed on it.
Wearing safety glasses, and either using pliers or rubber gloves, remove the blades and use a rag or a wire brush to remove the now softened paint. I some rare cases you will actualy get the chemicals that "eat" paint, and you won't have to do anything other than wipe them down. This is rare.
I use a splash backer behind a dedicated bench mount wire wheel when ever I do something like this, but most people don't have the wire wheel.
Rinse the blades in clean cool water and finish with wet sanding.
Personally I wouldn't do any of this until I have ground away the teeth from the blade, but then again some people want the teeth there, so its up to you.
As for treating after you have made your picks, go buy a bottle of gun blue. You can even get it in the sports section at Walmart. Gun black is a little harder to find, but works on a similar principle.
Have fun,
Romstar