Hey guys I just bought a new Alvarez pd80sc and it's kinda buzzing in some of the lower strings. I'm thinking about taking it in to the shop, but wanted to know what you guys thought it might be first. Also, am I supposed to have my guitar checked out before I play it just to make sure it's gonna sound the best?
I would definitely take it back to the shop you bought it at and have them set it up for you. It's brand new so they should do it for free.

And yes you should definitely try out any guitar before you buy to make sure it is what you want!
Errr....did it buzz in the store?
Fender Strat
Genz.Benz Black Pearl 1x12
Buzzing on lower frets usually means it needs more relief in the neck I believe, or basically loosening the rod by turning it counter clockwise.
If you bought it online you will quickly find out why online stores can be a bit cheaper than local stores: they don't usually set the guitar up for you and getting a shop/lutier to do it costs you around $60. It will be a decent investment if you can afford it though.
If you bought it at a store they should set it up for you for free, otherwise I would not recommend buying there again.

There are multiple guides online to solve buzz. I'm not going to post them all here since tinkering with it yourself is not recommended on a decent guitar, but if you take it to a skilled lutier they should be able to get it set up well for you. (I assume that's what you meant with your final line)
ok just wondering... how had should you have to push on the strings to get them to play without buzzing? I'm using .12 gauge Elixers and they won't buzz if I push very very hard on them. Only problem is it then leaves very deep marks in my fingers, dispite my callouses.
also, could it just be that i'm using a high gauge??? should i try to go down a little... what are the differences between gauges?
no. 12's are the standard guage for guitars. the difference is just the thickness of the string and the tension it puts on your guitar. higher guage strings like Mediums(13s) will give you more sustain because of the higher tension, which also means that it's harder to play.

As a beginner, i would very much encourage you to keep with 12s for a while. half a year maybe? It'll help you develop finger strength. When you have enough strength to play barre chords with 12s, then i'd say go as low as 11s. it makes quite a difference.

the reason that i will never use anything lighter than 11 is because the lighter the string, the more susceptible you are to pressing too hard and playing everything out of tune. you should only use enough finger strength to just get the string touching the fret. often when guitarists play however, they tend to tense up and start pressing harder. it's a hard habit to break, so try not to go too low on the string guages.

13 = medium \
12.5 = medium/light
12 = light
11 = custom light
10 = extra light(?)
9 = i have no idea what these are usually called.
these are the standard names for guages.

LASTLY. deep marks in your fingers. I have VERY deep marks in my little short stubby sausage-like fingers. dont worry about them. mine are actually permanently there. they dont disappear. they're just little grooves in my index and ring finger that just stay there encased in my callous. dont worry about the marks.
ok... well i've been playing guitar for about a year and i started with 11s and then switched to 12s. I just want to know if the buzzing is cause by me not pressing on the strings hard enough (i think i'm actually overdoing it because it is definitely more than just touching the frets) or if i need to take it back in and get it set up.
...Or you might have to hold the chord tighter. Always worked for me.
Avenged Sevenfold Fan, proud of it.
try testing for fret buzz. hold the string to the fret as close as you can to the fret and use the least amount of force you can to hold it down without it buzzing on the fret you're pressing. if it still buzzes, you may need a set up.