Since I have yet to see a tut on Screen shots, I thought I would offer my way of putting together a quality SS. While my style may not suit all, it can help those wanting hints/ideas.
HG's rules of screen shots:
#1. less is more. To me a screen should be functional as well as elegant. To much stuff within a SS can often work against the look im trying to purvey.
#2. Clean and smooth. The elements should fit well together and look like they belong, going by textures/gradients first. Colors are typically not as imperative, as they can be changed later.
#3. Obscure the wall enough to keep it hard to extract but still be seen well. Object placement can be critical as it should look as if it was supposed to be there to begin with, not like an add on.
#4 When Matching colors, try to adjust to match the main items majority color. I often use the DesktopX color Picker to get elements as closely color matched as possible. If an element fits well with the theme, the surrounding colors of it usually closely match the ones in the main item. * Hint try to match the brightest portions of the colored areas, the darker areas should fall in line* if not you can settle for a happy medium, if it is to far off then Id go searching for a more fitting item.
Building a SS from the ground up:
I will use one of my own screen shots and describe how I assembled it to better explain. ( Phoenix, at bottom of page)
First I spotted the wall By Sed. And decided I wanted to build a desktop to go with it.
So I grabbed A WB that just fit the look of the wall with its color scheme, texture and gradients. Which was October BY NightTrain. It was already close in color, the black fit well with the Walls borders, the satiny glow of the Orange set well with the satin look of the Wall. Next I grabbed the Matching docks by webgizmos and Widgets by fairyy~ from the Library as I felt those too would be a perfect match. The Round weather widget just looked like it fit right in the middle, which also offered more Obscurity to keep the wall from being extracted.
As for the Icons I wanted ones that really complimented the wall and WB's light contrasts, I chose Sunx's Dark Shine Icon set as they had little bands within them that once recolored really matched the wall and WB. It looked to me as if they were meant to be together, Kind of like finding the pieces in a puzzle.
So I moved on to the cursorFX. I wanted one that just screamed Pick me. Again the gradients and texture came in to play. JJ yings Cursors from his master suite fit the bill. Perfect style, coloring and with a flame like pattern to go with the Phoenix Wall.
Move things around to give a full desktop look without clutter. When satisfied all is as it should be, I Print screen, import from clipboard to Xnview, Save at Jpeg highest quality. * do not use progressive or optimize hoffman table as they tend to fubar the images* Upload to WC and Im all done.
This was actually one of the more easier Desktop combination's to assemble. But some times simplicity pays off. 
There are more complex Screen Shots I have done with actually making elements from the WB and or other items in the libraries, but that is for another day, another tutorial.
Other shooters, feel free to add to this with tips and or your ideas on how to build that perfect screen shot.
