Under Virginia employment law is it considered harassment if the employer grabs the employee and states that he owns them?

You'd need to provide more info; in and of itself it doesn't sound actionable as workplace discrimination or assault, and damages in any case would be limited by the fact that you had already resigned. For these reasons you won't likely find an attorney to take this case. You could try filing a complaint with the EEOC (link below), but probably best to move on with life.