I wish to put two small .png pictures (with transparent backgrounds), layoutet underneath eachother, in my Header area overlaying the Header Image. They should both link to other websites.

I was thinking about using the "Blog Title" and "Blog Tagline" to do this but are not sure how (i'm a newbie) -or perhaps there is a better way...?

Many thanks

Perhaps it also can be done with a Widget? But I not sure how to make a widget or get it in the header area!---Please help!

You can create a new widget area right along with the menu bars, header, etc. Go to ATO>Add New WIDGET AREAS and read all about it. You should really play around with this a little as it is easier to learn in doing that in someone explaining and the documentation that is there is quite thourough.