It is perfectly possible to add images; first, however, you need to
get the images into the project. Using Visual Studio (including
"express") you can drag files from Explorer into the solution explorer
(the tree with the files). Once the images are in the solution, there
are 2 ways to get access to them (in both cases, leave the build
action of the form as "compile")

The easiest option is to set the build action of the image(s) to
"content" (the default), and add a resource file (there may already by
one called Resources.resx) in the Properties folder. Open the resource
file (View Designer), and drag the image from the solution explorer
into the resource designer (anywhere... it doesn't matter). This tells
the compiler to embed the image into the resource file, which itself
will be embedded into the exe. You can now access the image by name,
simply by looking at ResourceFileName.ImageFileName - i.e. for me my
resource file is "Resources.resx", and my image is "Test.jpg", so I
can use Resources.Test (which is an Image). Using the same example, if
it doesn't compile (The name 'Resources' does not exist in the current
context) then right-click on the Resources (underlined in blue in the
editor), Resolve -> using [some namespace]. It should then work. Your
images should also now appear automatically when selecting button
images etc.

The second option is to change the build action of the image(s) to
"embedded resource"; however, it is trickier to get hold of these -
you need to use Assembly.GetManifestResourceStream({name}), and
process the stream manually.