My hard drive crashed, but I've got Match. How can I get all 12,000 tracks back?

I decided to go totally digital at New Year's and bought an external hard drive for my laptop and copied 400+ CDs to it. I also moved over my existing iTunes library and purchases to this external drive. I then subscribed to iTunes Match and sent all 12,000+ tracks to the cloud/Match and so I had my iPhone and iPad running my entire library, in addition to my laptop with external drive, which was great. For a few months.

Then the other week, my external hard drive just totally crapped out. I had a technician look at it and he says it's toast.

When I get a new external hard drive, what's the easiest way to get all my music from the cloud/Match (sorry if I'm getting the lingo wrong) synched to this new hard drive? I've been searching for the answer to this forever with no joy.