Note that as of Nov 2009, the PIC16F876 is no longer recommended for new design. This means that it will probably get discontinued at some point in the next few years. You may prefer to instead use a PIC16F886, which is pin-compatible. If you do, then make sure to specify the correct part when you compile, since the 'F886 is not code-compatible.
The microcontroller (IC1) is part number PIC16F876-20I/SP-ND at Digikey. Almost any three-terminal resonator (U1) will do; you might try a 535-9356-ND or an X909-ND.
The only thing that might confuse you is that the pushbutton goes to Vdd, and there is a pull-down. You might be more used to seeing a pushbutton to ground with a pull-up. For TTL, this mattered. For modern CMOS it does not, and I find this `active HIGH' arrangement less confusing than the traditional `active LOW' circuit.
Also, I chose to use a ceramic resonator with internal capacitors, U1, instead of a crystal and two ~20 pF caps. A crystal would work just as well and it would be more accurate, but it would be a little bit more expensive, and you would need more parts.
You could build this circuit in many different ways. I built it on a solderless breadboard, and it ended up looking like this:
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