Here is the url for that show:
http://notjustrockexpo.com/. It is probably a bit far to travel from California.
There was a rock and roll autograph show in LA that benefitted St. Judes, but from what I can tell they no longer have it. Here is the url for their facebook:
https://www.facebook.com/RocknRollAutographShow
Vinyl Times also has a calendar of record shows.
Years ago there was a group called Rock Ages that would have record shows in NYC. It took up a whole floor of the hotel across from Madison Square Garden which has had several names over the years including The Penta. It was not a normal record collector's show as there was a display of promo items - Elton John pinball wizard hat, presentation Jethro Tull 'Songs From the Wood' album made of wood and the such. They also had an interview area where Pete Fornitale, famous radio announcer, would interview people. I remember when he interviewed Harry Chapin who then performed a few unreleased songs. I have a photo of that on my office wall. There were many vendors selling vinyl and the such, no CD's then. There were also musicians around. Lenny Kaye (Patti Smith guitarist and creator of the 'Nuggets' compilations) was selling his own records. The Ramones had a merchandise table and they all showed up. I still regret not buying a Ramones logo flag. One of the best collector's shows I have ever been to and it was 40 years ago. I still remember taking the train down from Boston, going to an ELO show on Friday night at MSG, going to the show on Saturday and taking the train home on Sunday.