The main street in Sonora is Washington Street, which runs North to South. From the north, indicated landmarks here are:

• the Red Church;
• the Days Inn Sonora;
• the Opera Hall;
• the Gunn House;
• Inns of California

To get to the Youngstrom's:

1. Head South on Washington Street until you get to the first traffic light. Take a left, and then an immediate right, which will put you on Mono Way. If you miss the light on Washington Street, don't worry. You'll run into Highway 108, can turn left on 108 heading East, and be back on track with Step 3 here.
2. Follow Mono Way for a couple of miles until it ends at a traffic light at Highway 108. Along Mono Way you'll pass an Orchard Supply Hardware on your left, followed by Andy's Hardware, and Save Mart Supermarket on your right.
3. Turn left onto 108, heading East. Again, you'll go for a mile or so. You'll pass a faux-Mexican restaurant called Peppery on your left; you'll go straight through a traffic light with a right turn for Tuolumne Road; you'll pass the Junction Shopping Center on your right.
4. Opposite the Junction, just past the turnoff for it, there's a left turn, with no traffic light, for Phoenix Lake Road. This is just past a Shell Station and a Burger King on the left. Turn left onto Phoenix Lake Road.
5. 2.5 miles down the road on your left you'll see Phoenix Lake. A few hundred yards after the lake, the road will bend down and to the left, and you'll see a turnoff for Old Phoenix Lake Road. There's a broad, triangular gravel patch here created by the fork between Phoenix Lake Road and Old Phoenix Lake Road. This might make a good place to park, by the way.
6. Almost immediately after turning onto Old Phoenix Lake Road you'll see a yellow newspaper box at the head of a gravel driveway on your left. This is 20892, the Youngstrom residence.