Deelguy is a land to the northeast of the Beklan Empire in Richard Adams novel "Shardik". I don't remember the story enough to say how it figures in the book but it has always been a name that I've liked. Some authors either don't have the imagination or are too lazy to come up with good names. Nowadays when I see a fantasy novel I always check to see if there is a map. If there is I look at the place names - the cities and countries. If they are just rip-offs of older writers, or they look like they are put together with a random syllable generator I generally give the book a pass. (Likewise if it involves time travel or the characters speak as if they grew up down the street.) Eliminate those and there really are not that many fantasy novels out there that are worth a glance.
Richard Adams, on the other hand, did a good job with Shardik. I like the map! :-)