Tret, you already have a 120+ thread about buying a computer. There's no point in waiting. If you don't want to go with the top of the line, go middle-road with the most expensive components and upgrade them gradually as you need to. As someone in your original thread mentioned, there are static and there are dynamic components when it comes to building PCs.
The dynamic components are often the ones that fluctuate and depreciate the fastest (CPUs, video cards, HDDs, RAM, etc.) The rest is more of an investment that will be the core of your PC for some time, and will not need to be ugpraded much, if at all (monitor, speakers, keyboard, mouse, case, PSU, etc.) I would spend more on the static items and less on the dynamic items, as the dynamic items also tend to carry a much higher premium for marginal performance.
I would definitely not recommend waiting until Athlon 64 before upgrading. AMD has pushed the launch date of the desktop Hammer to September, but AMD also has a nasty habit of missing release dates. Also, the price tag will undoubtedly be extreme and there are still many questions regarding software compatibility that need to be answered. Its going to be an immature platform for some time, with many of the planned motherboard features being pushed into 2004 (PCI-X, DDR-II, etc.).
If you wanted to wait a reasonable amount of time for something worth waiting for, you might want to hold out a month or so for the 800MHz P4's and the release of Canterwood motherboards. Otherwise, Socket A Athlon or any P4 will give you performance today with upgradability in the future.
Chiz