Hi,
I bought my Lensmate and had it shipped to me here in the UK. You have to use Paypal to purchase it and they send it USPS. Mine arrived in less than a week in a large box (considering the size of the adapter) filled with polystyrene chips.
I was a bit skeptical about it all but I can't fault their service.
The only hassle is registering the Paypal account . . .
I think you can buy Canon's own here but this is a 58mm adapter. If you use the viewfinder this adapter will block more of the viewfinder image. Likewise with the internal flash. If you use it with Canons adapter in place it blocks a hell of a lot more flash than the Lensmate.
Carl