Street Map Wood Inlay

I saw these wood map inlays online and wanted to make my own using the laser cutter at Techshop SF.  I found a street map of seattle and used it to generate a vector file, which I then laser cut and stained.  Eventually I would like to glue this map together and use it as the surface of a coffee table.

Unfortunately you cannot export vector files straight off of google maps, and I couldn't find a great alternative anywhere else online (of seattle specifically).  So I went to woodcutmaps.com and used their online map generator to create my own map.  I took a screen shot of the final map and imported it into photoshop.
A word of warning here- I spent waaay too many hours getting this map right in photoshop.  It's mostly my own fault for being a perfectionist, just be aware that it will take a lot of tweaking to get the results I did (you can download my eps file below).
Basically my process was to compile the screenshot from woodcutmaps with a few screen shots from google maps (for extra detail), and use the magic wand tool to extract three layers- water, street, and land from the images. I used the "refine edge" option of the magic wand to make sure I was generating smooth, high-contrast edges.  I also ended up using the line and rectangle tools to draw in a fair amount of the streets by hand.
Eventually I ended up with three layers of color (fig 7).  I exported each layer as a png and imported them in illustrator.  I used the live trace function in illustrator to generate outlines of the shapes and export as eps (attached below).

I laser cut the map out of 0.25" birch veneer ply on an epilog 120W laser cutter at Techshop SF.

I used minwax cherry 235 stain to stain the "land" areas a medium color, and the "water" areas dark (used two coats of stain).  I left the "street" areas unstained.  I removed each piece and stained them individually so that I maintained very crisp color contrast at the edges of adjacent pieces.  Unfortunately, not all of my pieces could be removed for the staining process (the ply was slightly warped, which causes trouble for the laser cutter), so I had to rely on painter's tape to keep stain off some of the "street" sections, and there were a few places where it bled through (if you look closely at figure 5 you might be able to find it).  All in all, it looked pretty good.
Once I find the right sized coffee table, I will glue down the pieces to the surface of the table and finish it with a thick clear coat to seal everything together.