I have 3 strats... a 60,s reissue .. a white mexican strat with 60's pick ups.. and a guitar I built myself, modeled after Stevie Ray's old fender (with the Tex Special pickups and the reverse tremelo)
Do like most of us..buy a tuner..chromatic digital tuners are the best.. it'll show you the note of each string as well as make it easier to experiment with alternate tunings... <img src="images/smiley_icons/icon_biggrin.gif" border=0 alt="Very Happy">
I have to correct myself here (before someone else does!..lol.. the twelfth fret is halfway between the nut and the bridge! haha
Anyway..hope the info helps....
this is a bit tricky... but tune your guitar as normal... then with a really good tuner, hit each string at the 12th fret...if the 12th fret note is the same as the open string, the intonation is fine...if the note is high or lower then you have to adjust the saddle... hypothetically ..The distance between the first and twelfth fret, and the twelfth and bridge should be identical ( except on the B string on (some) guitars)after that.. as for the clicks and buzz, you can raise the action by adjusting the height screws on the saddles just a little, and see if that works..if you have to raise the strings to an uncofortable level to play..then your neck may need adjusting..to check that, you can take a ruler or yard stick and lay the edge to the fretboard.. it should touch all of the frets.. if your neck is bowed it will kill the intonation as well... have a pro fix that!