I worked for an employer from 1994 until 1998. I paid into a 401k while I worked there. When I quit in April of 1998 I never thought anything of it, asumed it was just gone. I had never received any corspondance about it at all. Recently this topic came up and I was told I might be wrong about my asumptions. Any advice?

Contact the employer. You may have forfeited any company match, but your contributions are always fully vested.