"On July 15, for example, a group of villagers from Marwahin left the area in a convoy, in part because Hezbollah was attempting to store weapons behind their homes, and residents feared a retaliatory IDF strike.9 Two rockets believed to have been fired from Israeli helicopters struck a white pick-up and a passenger car in the convoy on the road between the villages of Chamaa and Biyada, killing twenty-one civilians (see 'Attacks on Fleeing Civilians'). A U.N. team trying to retrieve the bodies came under fire from the IDF.10 While the villagers’ flight could be attributed in part to Hezbollah’s unlawful attempt to store weapons in Marwahin—the main reason for flight was the Israeli warning to evacuate within two hour—Human Rights Watch found no evidence to suggest that Hezbollah fighters were near the civilian convoy when it got hit.
"Christian villagers fleeing the village of `Ain Ebel have also complained about Hezbollah tactics that placed them at risk, telling the New York Times that 'Hezbollah came to [our village] to shoot its rockets.… They are shooting from between our houses.'11 `Ain Ebel was a former stronghold for the Israeli-backed South Lebanese Army (SLA), a force opposed to Hezbollah. According to an official from `Ain Ebel, some villagers told him that Hezbollah had fired at Israel from certain positions close to their houses, although so far Human Rights Watch has heard no reports of Hezbollah entering any village homes. No villagers have died but a number have been injured (mostly from broken glass), and Israeli fire had destroyed roughly eighty of 400 houses, he said.12.
"Human Rights Watch is hardly asserting that all Israeli strikes have targeted civilians. There are obviously many cases in which Israeli forces attacked legitimate military targets, such as rocket launchers and dug-in military positions. However, in the cases documented below, no apparent military objective existed in the civilian houses that Israel attacked. Villagers interviewed privately in one-on-one settings stated credibly and consistently that Hezbollah was not present in their homes or the vicinity when the attacks took place, and Human Rights Watch found no other evidence to suggest that Hezbollah had been there."
You'll have to go through those cases yourself (including an account of Qana), as there's no good way to excerpt them. It sounds like Israel is acting on a lot of questionable intelligence, striking anything they believe might be a Hizbullah target, such as vehicles fleeing target areas which they fear might be carrying something they want to destroy. They are also not limiting themselves to attacking Hizbullah's military wing.
(Hat tip: Juan Cole)