It is very simple to set up a RAID array. Just follow these steps:
1) Plug in the two drives you wish to RAID and no others.
2) Go into the BIOS and find the HDD settings, (It should be on the same page as where you choose whether to use AHCI/IDE) and choose to enable RAID on the ports that you have the drives plugged into.
3) Exit and save changes. When you boot up next you will be asked to enter the RAID set up. In here you need to select the drives you wish to RAID together and what array you want to use. For speed, you want RAID 0, or a striped array.
4) Save and exit the RAID set up and install Windows. Windows will recognise the two 60GB SSD's as one 120GB.
Hope this clears it all up for you!