I'll chime in here...
The JDM and all those other old programmer designs are pretty much defunct now.
They mostly have interface problems, timing issues and really don't like modern PC hardware, they had their place and time, but no longer. If I desperately had to build a programmer to burn a one off device out in the sticks somewhere, I may well put together something like a JDM or PicPro etc with a couple of transistors and resistors etc. It won't be particularly reliable, but may get the job done at the time.
The value in a decent programmer cannot be understated. Whether you choose a Microchip PICKit2, a clone of some sort, or a professional programmer like the Xeltek that I have matters not. What matters is that the programmer is consistent and reliable, allowing you to concentrate on what you want to do with it, rather than wondering if a device didn't program because the serial port doesn't quite cut it, or the programming voltage fluctuates just enough etc. A decent programmer also has regular support from both the manufacturer and the community and may even have added features like a small logic analyser as in the case of the PICKit2 et al, or a logic chip tester like my Xeltek has.
If the genuine Microchip PICKit2 is too expensive for you, look into the Junebug from Bill at Blueroom, or a straight PICKit2 clone from Sure Electronics. If I were to choose between those, I would have the Junebug on account of it's added features, however both are reliable and consistent programmers, have good ongoing support and features and will allow you to get into your project immediately.
rgds