If you want a better guide, here's one I just wrote. Save up $400-600 and have someone else build you one.
No one is going to spoon feed you. A lot of this is up to you, and what you want from your N64p. You need to have at least a rough understanding of what you're doing, so if something goes wrong, you can either fix it or describe it well enough that someone else can help you fix it. Read, read, read. Read the stickies, read work logs (especially older ones), use the search, and then ask questions. None of this stuff is rocket science, it just takes a little work on your part. If we can tell that you're actually trying, people will be more than willing to help you out.
You will find that this forum can be very blunt. Be prepared to take some criticism. It is (usually) only done to make you better.