any chance you can share your recipe for the starter or did you purchase it somewhere? I need to use my bread machine more.
Sorry for the delayed response.
It takes about a week to get a starter going, after that, just keep refreshing it once a week.
Take 1-2 tablespoons of whole wheat or rye flour (rye is best) and mix with enough water to make a thick 'batter'. Don't sweat the details here. Equal weights of water and flour. You don't need much, maybe a 1/4 cup. Leave that in a covered (not sealed) container for 24 -36 hours.
After 24-36 hours, it won't look like much will be going on; that's fine.
Toss half of the mix into the trash.
Add equal parts water and flour to the remaining half and mix. Again, you are looking for a thick batter. It's better to err on the wetter side.
Set aside, covered, not sealed, for 24 hours.
At this point, you might start to see some small bubble forming. If not, don't worry.
Toss half the mix and add equal parts water and flour to make a thick batter. Set aside for 24 hours.
Hopefully the mix is starting to form bubbles at this point. If not, keep discarding half and adding more water & flour. After 7 days, you should definitely have a lively starter.

Keys:
1. Rye four is naturally higher in yeasts and lactobacilli, so it is a great flour to use. If not that, whole wheat is the next best choice. (once the starter gets going, you have established your micro-flora and can switch over to what ever flour you like the best.)
2. You must, must, must, MUST, use de-chlorinated water. Chlorine is a sourdough starter killer. I spring for spring water, but you can just boil some tap water and then leave it out for 24 hours, the chlorine will evaporate out
3. Initially keep your starter at room-temp (cool) and in a dark place. Sunlight kills starters, too. Once it gets going, store it in the refrigerator and just 'feed' it every week or so.
This is super easy. Mother Nature does all the work. But, it can take a few day to get going. Be patient and persevere.
