Adding another SSD to current rig

Hello Tribesmen!

I have never dealt with Raid and I am looking to switch over my rig to all SSDs...so I come to you brilliant folks looking for answers!

So my current setup is this:

20-148-441-ts_medium

One 64GB SSD for my OS and programs. I have all my files such as music, videos, and documents on a 500GB HDD.

I am looking to replace my HDD with this:

20-148-443-ts_medium

Is there anyway that I can make the computer think that I have a 320GB SSD and combine them rather than have everything seperated like the way it is now. Thanks for you help guys.