I need to have one page display the types of cars and the user selects from a dynamic drop menu. Then they click the Submit button that will open a page with the results. Is there a tutorial for this easy task?

Hello,
You can either do this on the same page, and filter your results data source by the selected value or if you want to use a separate page, just send the value using url variable (let's say your drop down is called "carType" then the button can just be:

 <a href="detailpage.php?carType={{$FORM.carType}}">Submit</a>

And on the detail page just filter your data source by the same url variable $FORM.carType

How do I create the dynamic dropdown though? I can't seem to figure it out.

Please check the video tutorials - all is explained there:
1. Creating a dynamic dropdown with static/empty first option:
www.dmxzone.com/go/22329/dynamic-drop-down-list-with-static-first-option

2. Creating a dynamic dropdown
www.dmxzone.com/go/22136/creating-a-dynamic-select-list-using-html5-data-bindings