Amy,
You’re absolutely right when you say, “maybe they're doing something more sophisticated”. The type of thing you are talking about doing can easily be done with a server side scripting language like PHP or ASP. The reason you mentioned above is the very same reason that I switched from using SSI to PHP. On
my company’s Web site I have navigation coded only one time, but based on where you are within the site it highlights the current directory.
It sounds like you are ready to move up to the next level of Web design, which will give you much more freedom and control ...And you can do a lot with just the simple stuff, like IF-THEN statements. The way it works is that you include a file, just like with SSI, but that file has dynamic elements to it. For instance, in the menu on my company’s website I say, in effect, “If the directory is ‘this’ then display ‘xx’ or else display ‘yy’”.
It is not too difficult to learn to do very simple programming like this, you just need to get a good book. The best way, I have found, to pick the right book is just to Borders or Barnes & Noble and simply flip through them and find one that has examples of how to do the things you want to do. There are also tutorial sites, but its generally harder to find everything you need. However, if you have more time then money then just look for the free stuff online. I have neither but what I have the least of is time ;-)
You also need to decide which road you want to take. If you will be working with large companies or are generally hosting your sites on Microsoft IIS servers, then ASP is probably a better choice. However, if your clients have tighter budgets or you find yourself hosting your sites on Apache servers, then PHP is probably a better choice; as it is free, “open source”, and there tends to be much more free scripts out there than ASP. The good news is that they are very similar so, whichever you pick, you can easily switch later.
There’s also ASP.NET, but you need to know some ‘hard core’ programming for a lot of that. Unless you plan on learning C# or VB programming, I would stick with the other two.
Hope that helped.