WMD wasn't the only reason. And there was plenty of evidence.
NBC: Secret U.S. mission hauls uranium from Iraq
Saddam Rewards Suicide Bombers' Families
Remember the whole Valerie Plame outing scandal. At the heart of that was Iraq's attempts to buy yellow cake Uranium.
I remember TV coverage of Saddam paying suicide bombers families long before we invaded. Saddam was constantly bragging about his nuclear mujadiheen.
Saddam was a medium + level bad guy. There were and still are worse regimes. I remember propaganda stories though, about Saddam in real time, holding up fingers as each plane hit a target. I never have seen it on video. I have heard it reported that WMDs were found, but GW never proclaimed it while he was being hammered by the press over his assertions.