Some things should be made from mild steel (tongs for example). A number of people use tool steel for tongs, but you have to watch out when you are cooling something you are holding with it!

I took a tooling class at the folkschool and the instructor's approach was to use 1045 steel for most tooling (it's cheap, you can harden it, and it does not need to be annealed. that makes it very forgiving). THe downside is that the tool will not last as long as if you used S7 or so (you get dozens of uses rather than hundreds) but as a hobbyist, something like that may last me a few years!

Another goodie is jackhammer bits. There's always some showing up in Iron-in-the-Hat.