you're on the right track. all you can do is scan CL, autotrader, eBay, etc., each day and when you find what you want move quickly. have your funds ready to go, organise a proper PPI and have your banker ready to move money.
the first NSX I wanted to buy back in '07 was a '91 red/black top with ivory interior. it was in mint condition in North Carolina with 80,000 miles for $24,000. it sold before I could get there. I found it on autotrader.com
the second NSX I went to buy about 9 months later was in Washington D.C., found it on Craigslist. it was a red/tan '96 NSX-T with 56k miles. flew there, had it checked out and made plans to purchase it, but the seller changed his mind when I was at my bank about to transfer funds. he was asking $38,000.
about 6 months later I found another red/tan '96 NSX-T on Craigslist. I found it the morning it popped up and flew to Denver, CO the next day to look at it and check it out. It had 40k miles and was in perfect condition, so I bought it for $40,000
it took me almost 2 years to finally purchase a clean, stock red NSX with a manual transmission.
I kept that car about 3 or more years and sold it for a profit with almost 30,000 more miles on it, as I wanted to get a 2002 to 2005. it took me almost 6 months to find another NSX that I wanted. I was originally looking for a red/tan again, but couldn't find one. the 2002+ are a lot more scarce than the 1991 to 2001 models. I was looking in all the usual places and I remembered seeing an "Imola orange" for sale on Prime and on autotrader in the recent past, so I asked a few guys on Prime if anyone remembered the car and I was pointed in the right direction of the owner. turned out it was in Denver, CO. exactly where I had purchased my first NSX. long story short, I flew there, had it checked out at the exact same dealership in Boulder by the exact same technician who PPIed my '96 and made arrangements with the seller to purchase the car minus the dollar amount of maintenance stuff it needed done.
my current NSX came through Prime, and both of my cars were bought in the Denver/Boulder area and checked out at Flat Irons Acura. the red '96 I shipped to Florida, and the '02 Imola I drove to California...