Many times when people are searching for Margret Roadknight they ask for Margaret Roadknight.

And, while I think Jim's suggestion and list are valuable, I offer a couple of comments.
Didgeridoo (Australian instrument), not didjeridoo, didjeridu, digeridoo, didgeridu, dijeridoo, dijeridu, etc.
"didjeridoo, didjeridu, and didgeridu" are all acceptable, as orthography for words of Aboriginal origin can be very flexible and all of these have been used in formal, academic, publications.

Shanty (a roughly built, often ramshackle cabin; a shack)
While this statement is true it is not complete in the Australian context, where it also, correctly, refers to a (usually maritime) work song.

This is where the suggestion of Jim's needs to be accompanied by a bit of experience in cultural variation. I have no interest in "bashing" but the points made above, where "Grey" is correct in some provenances and "Gray" is correct in others, illustrate the need for such experience. My browser (although US in origin) is indicating "Gray" as "incorrect" as I type but, having received a thorough education I can ignore most spellcheckers' recommendations with confidence.

I have seen US 'catters quote British and Australian writings where I know the author would not have used US spellings; I've also observed British and Oz writers treat US writings with the same disregard. It irks me but I'm known as a recidivist pedant.

While the DT is located in the US it seems reasonable for it to concentrate on US spellings but, if it is to cope with the international searches fluidly it might be helpful to either list, separately, alternate (but individually correct) titles of variants (preferred where the variants are sufficiently different from each other in text and/or provenance) or list all the variations in titles as part of the title where the differences in text and/or provenance are trivial. It seems that both seem to be happening to some extent. Which works most of the time.

Cheers, Rowan