I've figured out why I'm getting so many visits from people searching for "Delta Goodrum". It's because I've misspelt Delta Goodrem and so people who also misspell it (by putting a u into the last name where the e should be) have a greater chance of getting my page (or another page which similarly misspells the name) than a proper site. The influx seems to have stopped now - perhaps everyone else but me can now spell.
I'm sure I looked it up when I first wrote it, but I guess whatever site I looked at had also got it wrong.