web site structure

Hi guys,

I'm on my way to designing my third website, and was wondering if you could help me with a couple of queries. The first two were kind of off the bat efforts first one with a bit of dhtml and then another using some php scripting. One of my main problems though was the site structure, in terms of how files etc were organised on the server. I never really gave it much thought and it proved to be quite a pain after the sites got to be larger than a few pages.

can anyone recommend some good tutorials/articles/books about designing the structure of a web site?
also
can anyone recommend some good software(i'm on a low/pretty much zero budget here) that i might be able to use to help me design a site map/structure.

thanks

Andy

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