I made this in Sketchup for 174's pit
http://www.chiefdelphi.com/media/photos/36165
It has our team number clearly visible and a list of all sponsers. The design of the pit is mostly a "wall", so we are able to have as much of the 10'x10' space to work on our robot. I alloted room for the tool benches that hold all supplies meant for repair or sharing with other teams and a table. The blue banners show off our achievements. As a rookie team, you might want to consider having a location for photos as your achievements, or have a computer show a slideshow. Additionally, the whiteboard on the right pannel lists our wins/losses for the regional and will host a pamplet for teams to pull out, read and take with them for scouting.
A successful pit doesn't need to be flashy or expenisve - it just needs to do the job of showing off who you are and function as a place to repair a busted bot.