Okay, wasn't sure if anybody really wanted to hear the details.
To start, I googled "Walther logo" and looked on the images page and grabbed one of the highest resolution logos that I found.
Once I had the image I opened it in Photoshop and selected the white background. I then inverted the selection (CTRL+SHIFT+I) and dragged it using the move tool into the other pic that I took of my gun. That gave me a black logo that was a bit big. I just resized it on that layer and presto. It took about five times as long to describe it as actually doing it.
As far as the photo I placed a grey/blue 16x16 floor tile on my garage floor and put it at the very edge of the floor just under the door. It was a rainy day but still pretty bright so there was a ton of nice difuse light. I actually snapped the pic handheld with a small Sony digital camera (3.1mp?). This was one of about 14 shots/angles.
For post processing I cropped the photo and ran an unsharp mask command to sharpen it up a bit. There was no need to mess with any levels, or saturation as the camera did a pretty good job for a change. Most of my photos I do some retouching, but this wasn't too bad.
In reality I wanted just to post a quick pic and took advantage of the family being out of the house and the light conditions. It rained on and off all day yesterday but there were short periods where it stopped and brightened up a bit. I lucked out and managed to catch one of those periods.
A while back when I had my DSLR I did a lot of these kind of photos and they were all shot from a tripod with a remote release. The real difference being in that I could go with a narrower aperature and increase the depth of field. I hope to get another good camera and go back to being able to do that kind of work.