I used searchtempest.com and I think it is the best, it doesn't send an email but IMO it's the quickest way to search the country. I turn off the ebay results, choose 'any' distance, choose car+truck, enter the vehicle I'm searching for. Entering a number like 400 into the low side to weed out people trying to lease the 2nd Gens and a number in the high side for people trying to sell the car for too much. I skip the autotempest part, then once it gives the first search results, I click on display options, max out cities per page and I think that pulls 100% of the US into 9 pages and is really quick to look through.
Hope this helps. I'll be perusing for the manufacturer produced electric cars in 10 years if their batteries are worth anything at that point or if I can change the battery out economically or just outright rip the battery or other drivetrain components out to repurpose them.
...but I think nothing beats searchtempest.com They used to have a better search method where it displayed every single city on one page and automatically removed the blank results, but the CL lawyers turned the site into what it is today, which IMO isn't too bad.
2000 MT Insight "Silver Sipper"
2000 MT Insight Silver "Clone"