As I've mentioned before, I don't make soap. I use it though for laundry, for my hair, for my body and if I could find a formulation that worked well with dishes, I'd use soap for that too.
I read a lot of books about soapmaking. Even though I don't make soap I'm fascinated by the process and actually E and I do plan to make some sometime soon.
I just finished reading Soap: Making It, Enjoying It by Ann Bramson, it's not very expensive and it's a good book from the early 70s. Not the best book to start with if you want to start making soap, but if you want a clearer idea of how it's made, the history of soap and some tips on making pretty handcarved bars from a simple box mold, it's good. The reason I don't think it's a good beginning soapmaking book is because soapmaking has come a very long way since the mid-70s, the internet, people sharing information, the fact there is so much more information than there was then means that a lot of the information is out of date. Like she says to put the water into the lye in a glass juice bottle which can be dangerous. More current books explain how to mix lye into water more safely.
But the sheer amount of information on the history of soap was a lot of fun to read, and unlike a lot of how to books, her writing style is accessible enough I was able to read it from cover to cover instead of just reading the parts that looked interesting. Soap is a passion for her and her book was one of the first really good ones on soapmaking. Another thing is that most of her soaps are tallow soap, which means rendering fat to make the tallow. I like tallow soaps. In fact an awful lot of current formulations by major soap companies contain tallow, which makes for a nice hard bar of soap. More modern books focus on vegetable and nut oils that don't need hours of boiling and straining and have no animal by-products.
I've gone into detail about why I like soap, real soap over detergents. At some point I'll have to work on a list to ask soapmakers so you can know what you are using and buying. I usually ask if it's hot or cold process (cold process soap isn't boiled after the lye and fat are mixed, it's given time to age and fully cure to be usable, hot process is boiled to completely saponify all the fat and lye mixture and is usable as soon as it sets), if it's super-fatted (which means fat added that isn't saponified) and what additional ingredients are in it and if it uses essential oils or fragrance oils for scent. I will buy soaps that use fragrance oils, but I like to know for sure. Rose and jasmine soap from cottage industries almost always use a fragrance oil because their essential oils are really expensive.
For store bought soaps, there are a couple kinds that are real soap. Little House in the Suburbs says that Ivory is a good substitute for handmade soaps because it's inexpensive and only has a few ingredients which is what you're looking for in real soap. Mike uses Dr. Bronner's exclusively, the liquid version which seems expensive, but a little bit goes a long way, and can actually be diluted to half water, half soap if the people in your family just can't resist using lots.
One thing that Ms. Bramson recommended in her book to cut down on soap usage was not running the bar across your body and keep it all wet in the shower or bath, but using wet hands to soap up your hands and using your soapy hands which keeps the soap from being too water-logged and helps it last longer.
I love using my soaps. Other than Mike, we mostly use Gladheart Acres soap, which is cold process. We buy several bars at a time and the kids sniff them and pick out their soaps carefully. They love the whole process of it. We use end-cuts and mistakes from them in our kitchen and by our bathroom sinks for handwashing.
I'm reading another book on soapmaking now in between working on my current project which is pin cushion that's just turning out too cute. I should have that done in a day or two to show off and post general instructions for on Beadwork at Bellaonline.com.