Arduino Uno R3 3D model
An Arduino Uno, Rev 3 in solidworks
Dimensions taken directly from product data sheets and the EAGLE files for the Uno Reference design, so the model ought to be accurate.
Otherwise and as always with my models, it's probably useful to suppress the extraneous detail if it's not needed.
Steve Polus pointed out that I missed a component on the original and as it's nice to be right I added it. The decals for the board are also separately downloadable as BMP files, hope this is useful for those not in Solidworks land