Reddit mentions of California Atlas & Gazetteer

If you ask for GPS, rental car companies will give it to you, but expect them to charge you a ton of money ($5-20 per day). Use a smartphone and save the money. Also find a mount that makes your phone easy to use in any car and is easy to travel with (I like Tetrax).

Also, if for some reason google maps doesn't work out, don't be afraid to go analog.

Yes, the DeLorme challenges are based on the state map books DeLorme published (such as this one for California).

However, you don't really need a copy of the atlas to do the challenge - which is good, because Garmin (the GPSr maker) just purchased DeLorme, and said the atlases will no longer be published in print form.

The challenge is to find at least one cache for each "page" of the atlas. Specific details vary by state - in some cases, a page might be optional (because there aren't caches there). Sometimes, if a page has a smaller inset map, you'll be required to find a cache in the main area and in the inset; in other cases, finding something in either is sufficient.

The easiest way to check these is to use a challenge checker at Project-GC (search for "California Delorme" or similar), or use the statistics functions at mygeocachingprofile.com. Either one will generate a map showing what areas you have/haven't found.

I've been working on my state (Virginia) for about a year - along with the City and County challenges - and I'm finally at the point that 3 cache trips should finish it off. It takes a decent amount of trip pre-planning to pull these off... but some folks (myself included) find it fun to work towards.

OnX is either phone or GPS based maps. You can get 1 time purchase GPS or a subscription. If that's too expensive now a Gazeteer is a brand of paper maps with ownership info.

Mossberg 500 series is the basic and cheap but good pump shotgun. Remington 870 is another decent one (I own one and no major issues) but quality control has been down lately.

Edit: California gazetteer: California Atlas & Gazetteer https://www.amazon.com/dp/0899333834/

just about any state you want ....

https://www.amazon.com/California-Road-Recreation-Atlas-Benchmark/dp/0929591496/ref=sr_1_45?ie=UTF8&qid=1486500907&sr=8-45&keywords=map+atlas+usa

https://www.amazon.com/California-Atlas-Gazetteer-Delorme/dp/0899333834/ref=pd_sim_14_60?_encoding=UTF8&psc=1&refRID=BZFWVQPP8M10HWEC13BK

have a mind to download or print? ....

https://drive.google.com/file/d/0B6-eYcf1HwPUUnNwTE00WXlLMkE/view

https://drive.google.com/file/d/0B6-eYcf1HwPUbUZ4WlBDNnpsc2c/view

https://drive.google.com/file/d/0B6-eYcf1HwPUZkZtX3d1aS1Ybjg/view

https://drive.google.com/file/d/0B6-eYcf1HwPUdGY0ZUtEbFY1MlpjS2JQWHU3Y0lsYWZqMHBJ/view

https://drive.google.com/file/d/0B6-eYcf1HwPUOFFSQVdhd0hiVm8/view

http://www.abandonedrails.com/

http://trains.rockycrater.org/pfmsig/atlas.php

This is what you want...