A Blog Question

I’ve been trying to get a image into my Post Header on my blog, but
can’t quite get the code right for doing this. I got word that
there’s some wizards out here that knows this stuff.

im using blogspot.com if that matters.
please o great blog-monster. spew out your codes for me,
and let my outlay rip trough the standard outlays in all
eterenty. :)