Hi there pursey,
That is really unpleasant.
If the data stored on that drive is extremely important, you will need to look for some professional help. You can check WD's Data Recovery Partners out: http://products.wdc.com/support/kb.ashx?id=psGjuu
Unfortunately, as the other guys have already suggested, you've exposed the drive's platters to dust contaminated environment. The data may not be recoverable and it is not fixable.