I'm looking forward to Katie's variation on a homemade laundry soap.
There are variations that are just powder and some that are gel. Some add small amounts of blue dishwashing detergent, some with oxy products.
It's just DH and I now, so we buy powdered detergent about once every 2 years and we use gelled homemade laundry soap most of the time.
For whites and sheets, I use powdered detergent, for everyday work clothes and play clothes, gelled laundry soap.
Gelled laundry soap
12 oz of shredded homemade soap (or use Fels Naptha or Ivory)
melt it in 3 quarts of boiling water.
Pour the melted (clear, no solids) soap into a 3 gallon bucket with 1 and 1/2 cups of borax powder and 1 and 1/2 cups of washing soda. Mix well, then add cool water to fill. Mix again about every couple hours until it is cool. It will turn into gel. I use 1/2 cup per load. (optionally add a little essential oil, like lavender or tea tree oil for a scent) Makes 3 gallons. Store with a measuring 1/2 cup and cover between loads with a lid.
Pros: Gelled laundry soap costs less than $5 and it lasts us 7-9 months.
Cons: Doesn't keep whites white, they get a little gray, which can be remedied with some bleach and detergent.
You can test to see if you are using too much detergent or not, by starting your laundry without detergent, if you are you seeing any suds, it's detergent left in your clothes. Then you can cut back on how much is used.
Laundry soap gel, doesn't suds, it's not supposed to.