Why isn't homemade hardware a thing
If you're talking about fabricating your own IC like maybe an Intel '386 or '486 processor "without specialized equipment" you can forget it.  However, the computer pioneers built the first computers with vacuum tubes, and there's nothing preventing you from buying a boatload of them and wiring them together to duplicate what they did.  Or, you could get a bunch of TTL NAND gates and build a processor with them. If you just want to learn about digital logic you don't have to go that far, you could experiment with some simple circuits, then take a course in Verilog or VHDL.  At that point you could implement a simple processor in an FPGA rather than wiring together a bunch of discrete gates.