You can see the buses available when you go in to assign buses but you may also see available buses without being in a trip.  This option is available on the Vehicle Owners tab and on the Trip Requests tab.  The vehicle owner tab is only available to individuals assigned as vehicle owners in the setup table.  The trip request tab is only available to admin users.

Click on either the Vehicle Owners or Trip Request tab.  Scroll near the bottom on the left-hand side.

Click on "Find Available Vehicles"

You may click any of these options; however, you may want to simply enter the date in question and "Find Available Vehicles"

You can enter the Leave Date and Return Date and Times and Type of Vehicles and click "Find Available Vehicles" - or you can use any of the other search options on the screen. You will also notice that there is a helpful video on finding available vehicles that you can click on and view.  

You will see a list of the available vehicles with specific vehicle information.