Does anyone out there know of a good solution to provide users of a website a database of autos that includes the make/model/year/options?

I'm not looking for a database or link to autos for sale. This would be a resource for users to complete when they post an auto for sale.

Did you try google.com?

here's one of my favorite. just select the year make model and click specs

http://www.edmunds.com

research price & specs