Graham Walzer Photography
Big Sur Bakery
Fernwood Bar/Resturant (see below)
Andrew Molera State Park - great campsite by the sea
The Old Coast Highway is amazing driving
Fernwood Campground has it all. There are great campsites by a river, cabins, and a yummy rustic bar/restuarant.
Esalen is a stunning cliff top retreat with clothing optional jacuzzis overlooking the ocean. You need advanced reservations to stay overnight BUT you are able to book at nighttime spa (11pm -2pm) same day for $30.
The Ariel Tram Ride is amazing. It's a well spent $25 bucks. In the winter it will be chillyyyy on top of the mountain - maybe even snow!
The Ace Hotel has a very good restaurant and bar called Kings Highway. It's open for breakfast, lunch and dinner.
The Salton Sea is about an hour from Palm Springs and is well worth the drive for weird exploration, abandoned towns and desert weirdos. Drive another 45 minutes and get to Salvation Mountain and Slab City. You will find things you've never seen before and meet some really interesting people. If you make it to Slab City, find your way to East Jesus and the Slab City Library.
Drive time between Palms Springs and Joshua Tree is 45-60 minutes. There is a lot to see in both Palm Springs and Joshua Tree. If you only have a day trip, I'd tackle just one.
Crossroads is a delicious healthy breakfast/lunch oasis in the desert. Eat there.
Inside the national park ($15 entrance fee) go to Jumbo Rocks and Skull Rock. Go to Key Point for sunset/sunrise.
Indian Cove is outside Joshua Tree National Park, in between "Downtown" Joshua Tree and 29 Palms. It's great for exploring the big hulking rocks, day hikes. Great place to camp if you can find a spot or make a reservation.
Have a drink/Dinner at Pappy and Harriet's. Sometimes there is music performances. Check their website to see.
Go see the Integratron and see if you can make a reservation for a Sound Bath.
Go find Split Rock, the largest rock in the United States.
Camping in the park might be difficult as its peak season. You could stay at Pappy and Harriet's. 29 Palms Inn also in funny and weird and they have a pool. Joshua Tree Inn also has it's desert charm.