The only view on the SD Card that is built into the phone as standard is from menu, settings, SD & phone settings... this will tell you the space on the card and the available space. (for example my 8GB card says Total 7.40 GB and 2.76GB free space)
To see the files on the SD card you can plug the phone into your computer with the USB cable and choose the disk option.
Or you can download an explorer app from the market. there are a few good ones. I use ES File Explorer, others on here use AndroXplorer or Astro.