I think my trussrod is a little messed up, and looking at a few guides they say the neck relief needs to be about 0.3mm from the 9th fret. So my question is, how the hell am I supposed to measure that? A ruler won't be much use, and I suck at estimating measurements.

Any help aprecciated.
Use a capo on the first fret, and fret the 15th fret (or whatever fret is at the point where the neck meets the body) with your finger.

Should be just enough to fit a credit card snuggly over the 9th fret.

That just gives you a general idea of how the neck is. It doesn't HAVE to be .3mm as things like personal preference, string gauge, etc. can affect things as well. Basically start at that point and raise/lower to what suits your playing style (without fret buzz).

Also, always adjust string height first by adjusting the saddles on the bridge. If you're not experienced with adjusting the truss-rod, you can seriously damage the guitar neck. If you still feel the action is way too high, and/or still getting fret buzz after adjusting the saddles as best you can, repost and we'll try to help you out further.
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