Beautiful Widgets and Weather Widgets Donate are your two good options for HTC Sense looking widgets. Beautiful Widgets used to look more like the Sense UI, but HTC made the developer pull it until he changed it enough.
Speaking of the developer, Beautiful Widgets has a great one. It used to be that almost every day, there'd be an update with new and improved features for us users. Now he's moved onto developing a Twitter app - Touiteur. But every now and then we get some update love still!
And, if you get tired of the Sense UI look, both have a pretty good selection of skins to choose from, though Beautiful Widgets has a better selection. I might be a little biased.