I don't know why but I love soap- especially all the natural soaps you can get now, I buy them all the time....but for the most part, I wash up with shower gels and liquid soaps or cleansers. Using a nice bar of pretty awesomely scented soap is more of a "treat" thing for me, especially on the face. And it does feel like it's really getting you clean! Whole Foods has a great selection, and two online brands I like are RiverSoap.com and PrettyBabyHerbalSoap.com I think the natural soaps, especially the ones loaded with shea butter and olive oil etc aren't harsh like detergent based soaps...
However, someone mentioned castile soap and I wanted to mention a face cleanser I just did a review on, by Desert Essence. It's called "Thoroughly Clean Face Wash" with green tea amd sunflower. There are two of them, the other one is for oily skin, it has more tea tree oil. The one I'm using is yellow and I love it. It gets all the makeup, even mascara, you use so little to get a nice silky lather and your face does not feel dry or stripped. The top 3 ingredients are Castile soap, olive oil, and coconut oil. I don't even need toner after this. It's great stuff!