Serious Eats - seriouseats.com

It is really pretty simple. Use a transparent container (a quart will do) so that you can see fermentation. Mix a dough using 60 % flour 40% water and o put in container. After 24 hours at room temp, discard half and add fresh flour and water in the same proportion (60/40). After a second 24 hours repeat. By day 4, you will see active fermentation (by the formation of bubbles). When you feed the starter on day 4 it should triple in bulk within 2 hours. That's it, you've made a "mother". At the end of day 4, take a walnut sized piece of the dough and add it to a new 60/40 dough and refrigerate overnight.

Now, make bread, and when you do make an extra lb of dough that you leave out overnight to become your new mother from which you can make a new starter. If you are not baking regularly, just keep your starter in the fridge and feed it (as above) once every ten days. You can safely freeze a starter (or a mother) for a month.

I"m so glad someone asked, because I was thinking the same thing - how do I get a starter? My question is this: has anyone who has made one successfully compared it with an old one from somebody else? I've heard that the flavor is better. It is always a better idea to get a portion of an old starter?

I think my wife got hers from the King Arthur Flour website.