***RESEARCHER MUST HAVE USED TURBOTAX FOR THE WEB TO ACCEPT QUESTION***
What kind of software can I use to create a website/web-application
like TurboTax for the Web?  I am a non-programmer but have web design
experience.  I want to create a website that would ask the user to
answer a series of questions and then depending of responses arrive a
unique answer.  (Essentially just a bunch "if, then" statements.)  I
am hopeful that there is a program that will let me enter in all the
conditional statements into a file and then have the site run off that
file.  My application will be simpler than turbotax, maybe a better
example is the kind of Help programs that come with Windows like
Printer Troubleshooter.  thanks!

Why does anyone need to have seen TurboTax online to answer this question? 

If you have web design experience, you know how to make forms. What
you do with the output of a form... well, that requires some
programming.
It'd be on the order of <form action="parsethis.php" method="POST">,
where parsethis.php is your logic...

I suppose you could use javascript to do what you want, but php is not
dependent on the browser.

If the website is dynamic (a choice immeiately goes to an answer),
that is javascript. You'd be surprised what you can do with PHP... :)
However, based upon wanting to do something like a troubleshooter: on
click, load the page for select.value where the values of the
<option>s in the forms can either be real urls or offsets or filenames
or numbers which are filenames...

Just an FYI to the asker. Please see an example at
http://www.pigroast.net/menupage.html
The menu and the page that comes up when you hit submit were all
created using a combination of Javascript and PHP programming. I
assume yours is a bit more in-depth, as it sounds like you want a
Wizard, with NEXT buttons, maybe? We wanted to do that on that site,
but the owner prefers the scrolling down through the page.

Watch how the descriptions of the checked items appear at the bottom
as a *summary*. There are also restrictions, such as a message box
when entering a number greater than 400 guests or selecting too many
entrees.

Thanks.  Yeah, I am looking for more of a Wizard-type application.  I
wish this type of capability was available in a software application
like dreamweaver or something.