This is a GREAT point about intonation! Make SURE To get a guitar that will intonate properly. Yet another reason to buy, if at all possible, from a local shop where you can try it out, and even have it "Set Up" and intonated properly before you take it home for the first time. If you buy a guitar from a shop, have it intonated and it still isn't in tune above the 12th fret for example, DON"T TAKE IT HOME.
As many players are brand new, here is a SUPER QUICK AND DIRTY GUIDE TO INTONATION.
PIck up a guitar and tune it. Play a bar chord at the 5th, 9th, and 12th fret. Any chord will do so long as your first finger bars all the strings so you can move the chord around. It should sound "in tune" at every position. If you notice it sounds out of tune at the higher frets. the INTONATION IS PROBABLY WRONG.
You may be thinking that you can't really tell if a chord is in tune or not. At that point, you really need to ask the luthier/guitar tech at the shop (not the salesman typically unless they are very cool, as they might be on commission). Or bring someone with you, an instructor, band mate, friends, etc. who has more experience and can help you determine if the guitar is a keeper. Sort of like taking your Dad with you to buy your first car. Having someone with experience is helpful.
Of course, this won't be feasible for everyone. Some folks have told me they don't live near any music stores or pawn shops and that they have no musician friends close by so they have no choice but to buy site unseen from the internet. For someone starting out, this can have problems. Sometimes, it's fine. Sometimes, it's not.
The GMC family here can offer advice, but you really need to be able to touch/play an instrument you are buying, and learning how to tell if it's crap (won't tune/intonate properly, neck is warped, frets are worn, etc.) is a skill in itself and comes with time and experience about like playing guitar does
QUOTE (maharzan @ Jun 12 2012, 01:54 AM)
A good instrument really makes you polish your musical talents. I own 5 guitars. They are pretty expensive down here with a minimum $500 or so (for a $200ish guitar). And even though they are expensive they are very low quality. I owned a JEM as my first guitar but guess what, it detuned a lot, intonation issues and whenever I posted a take, everybody just commented about something is wrong with that guitar. With like 6-7 years with the same guitar, my ears obviously trained badly. I never knew about intonations. My bends are still struggling, things like that. So, I really recommend getting a really nice guitar before spending too many hours with it.