I’m hoping to find a pre-made library including the ITG-3200 (3DOF one-chip MEMS gyroscope), to save me having to risk making one myself from scratch.
I thought the Sparkfun Eagle library (which, I might add, is awesome) would probably include it since they stock a breakout board for this chip, but it does not seem to be included in there 
Does anyone have any other ideas where I can find it?
Cheers.
Unless someone you trust has created it, you will have to check it thoroughly before using it. You might as well create your own, it would only take a few minutes with the software I use.
I’ve attached a lbr file with one I made. I don’t have the part to check it but all the measurements look good.
the Sparkfun’s one already has the ITG-3200 in
you can get the last version of the lib from here: http://www.opencircuits.com/SFE_Footprint_Library_Eagle