In Harry Potter and the Deathly Hallows, chapter "Xenophilius Lovegood", when Mr. Lovegood summons Death Eaters, they arrive using broomsticks instead of simply Apparating to his house. I did not understand this part. I know that upon arriving, the Death Eaters discussed that they were not in a hurry and it could be a false alarm, but all the same, isn't Apparition preferable than travel by broomstick, particularly for Death Eaters who were looking for Harry Potter so fervently?
I don't think this specific question is addressed anywhere; however, a general answer may be that his house might have had anti-apparition protection. As Dumbledore explained to Harry in Chapter 4 of Harry Potter and the Half-Blood Prince (my emphasis):
“Professor, why couldn’t we just Apparate directly into your old colleague’s house?”
“Because it would be quite as rude as kicking down the front door,” said Dumbledore. “Courtesy dictates that we offer fellow wizards the opportunity of denying us entry. In any case, most Wizarding dwellings are magically protected from unwanted Apparators. At Hogwarts, for instance — ”
“ — you can’t Apparate anywhere inside the buildings or grounds,” said Harry quickly. “Hermione Granger told me.”
This doesn't necessarily explain why the Death Eaters couldn't have Apparated nearby, but then again perhaps they did and only used the brooms for the last little bit.