Hi Jon
I'd recomend O1 to start out with. It's pretty common (fastenal carries it in bar stock), cheap, it's easy to work with hand tools, it's easy to harden and temper, and it takes a great edge.
I wouldn't go with found steel yet unless you have the capability to anneal it, and it will be less frustrating if there are less variables in the process
I started around a year and a half ago with a piece of s30v and had a horrible time with it (i've since gone to o1 as my main steel).
Feel free to PM me if you have any questions along the way
ryan