Sourdough update: My starter, Matilda, is strong and here is the bubbly bread to prove it. In case anyone wants to take on a fun, new hobby that's also delicious, here are some resource links:
For the starter I used:
http://www.kingarthurflour.com/.../sourdough-starter-recipe
And I didn't feed her twice a day until day 7 or so (not day 3) like the recipe advises
For the bread I used:
http://cooking.nytimes.com/recipes/1016277-tartines-country-bread
Happy baking!