Checking whether the funds are cleared can be done online. A direct deposit usually clears instantly.

debstar2905, have you specifically asked for a refund? If not, you need to ask them specifically for it. The funds should be in their account and they can refund you in seconds via an online banking service.

I agree that it does sound as though the seller is stringing you on. It's odd, though, given such a high number of sales.