Congrats on your pick of new pet. They are fun to keep and very prolific.
1. Are you looking for eggs, baby, juvies, adult and morph.
2. As I am sure you are doing your homework, they require a nice size tank (which your bro can assist you with)

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3. Depending on above size-- There are some in the Craigslist in Northern VA
https://www.gillywateraquatics.com/
https://www.ivysaxolotls.com/
This will get ya started if you have not searched already.
Keep us updated
Note: The ones sold as bait are actually tiger salamander larva (tadpoles) aka water dogs. I don't think they are for sale anymore because they would get off the fishing line and survive. Which would cause an overload of an invasive species into some of the lakes and streams.
That being said: CA does not allow them and I am no longer updated with fish and game rules for other states.