What you can find: Jasper of various colors, actinolite, chert.
Ease of access: Easy access from parking area.
Equipment needed: Backpack for specimens, hammer and chisel (and eye protection) if you mean to break apart the larger boulders.
Notes: This is a good site to visit in conjunction with the Salt Creek and Hearst sites
Safety considerations: If visiting in the summer, watch for rattlesnakes, and beware that black widows may nest under the rocks.
Where, exactly? At the junction of Tomki Road and Hearst Road, outside of Willits. Be aware, the ford where Hearst Road crosses the creek is washed out every winter, so don't depend on being able to cross that way!
Tomki Creek is a site often listed in the rockhound guides, not because the material there is particularly spectacular, but more because it's a convenient stop when one is going to the Eel River and Salt Creek locales.
Starting at the ford, you can walk downstream and pick up plenty of rounded actinolite cobbles, jaspers of various colors [red is quite common] and some very nice blue and green chert. Some of the red jasper occurs with a shiny, metallic-looking mineral, which I have not yet identified -- but it makes lovely specimens.
Upstream is less accessible, someone had strung a barbed wire fence across the creek when I last ventured up that way. Probably best not to risk the ire of the local inhabitants.
Although this site probably wouldn't be worth the trip by itself, it makes a very nice stop in conjunction with the Salt Creek and Eel River sites, since it's right in between the two. A half-hour or so of wandering around netted some rather nice pieces, and I think there'll be a lot more to be found after a good rain.