It's too late Klib.

You'll download all the OSTs

All the Character Songs

All the opening and ending singles

And

You

Will

Like

It.

Sigh...where can I buy them legally...?

Well there's importing from like cdjapan but that could get expensive real quick.

You might be able to find mp3 on the Japanese Itunes or Amazon stores. But getting the right to buys from those is a huge pain...

There's also ebay?

Sigh...this is what I get for trying to support the official release..

It's tough dude. I had to go through a struggle to buy a two song single off of amazon Japan.

Supporting Symphogear officially is indeed difficult. Last time I checked it doesn't even have a formal release in the West, so watching it via Crunchyroll the closest you can get to watching it "legally".
I do wish to import some merchandise eventually but it's hella expensive. There's a cool Hibiki figma that I've never seen under $80, plus I really want a Gear Pendant but those are also usually around $40 when I see them. They also just released a new Hibiki figure that's nearly $200 last time I checked, and this is barely scratching the surface.
So I have all the episodes and the soundtracks for Symphogear downloaded... through probably questionable means because holy fuck, trying to get it all legally is expensive and painful.

One day though, if NOTHING ELSE, I WILL get that Gear Pendant necklace.

I'd be fine if I had the Staples "That was easy" button, but it played Chris saying "Bang~!" instead.