It's probably easier to type the 30 lines...
Getting the resource itself isn't too bad:
Dim obj As Bitmap = My.Resources.ResourceManager.GetObject("MyPic2")
PictureBox1.Image = obj
Will do it (though you would probably want to cache the images in an array if you use them often as it returns a new image each time) - so all you have to do is generate the resource name "picOfBtn" + integer value in the loop.
But...then you have to loop through all the controls, identify the buttons you want to set an image for, get its name (Easy: the "Name" property will do that), break the name down to get the integer, build the property name string and then you can use the ResourceManager to get the image.
See what I mean? It's faster to do the lines yourself...