Well, I've had this guitar for awhile now, but just last week, 4 of the strings are starting to sound really bad. I don't know what it is, but when I play the first fret of the 3 highest strings, it sounds really tinny and oriental sounding, and it sounds absolutely awful.

Also, a day after that started happening, my 4th string started buzzing (well not really buzzing, but more like the sound I described above) when I played it open.

Any help would be appreciated.

im having a kinda similar problem with mine rite now but with only 1 string so i suggest change the strings that are acting gay
You may need to adjust the action.
--"Hey, don't worry; don't be afraid, ever, because this is just a ride."--
my friend had a smular problem with his guitar...his neck was screwed up maybe you striped that bolt or your broke a part of the guitar holdin the neck on so if its that you might have to get a new guitar...did you ever drop it?that might be the problem
Are these new strings by any chance?

If they are, get it in tune the way you want it, and fret the first fret quite hard. Usually when I restring I get a bit of 1st fret buzzing due to my really low action, but if I fret it quite hard so that the string bends a little around the fret (if you get me) it'll stop and sound like normal.

I dont think I explained that very well, but I hope its some sorta help.
Bring back Tabo
Well the strings are old. My friend was telling me that I just may need a new guitar. Oh well, i'll try changing the strings, and if that doesn't work... Time to break the bank
Your friend is stupid, you can most likely fix it.

Try adjusting the action and/or neck. Take it into a shop and see what they can do to set it up good.