Although they didn't invent the term, Old Timey was popularized as a term by the New Lost City Ramblers. It was their attempt to indicate the style of music that they were playing and to present it to a wider audience than just the folk officianados of the Fifties and early Sixties.

Bluegrass obviously came from Bill Monroe and the Bluegrass boys.

Old-Timey can be thought of as early country music from the twenties at one time labeled "hillbilly" music. I think that much of the traditional ballads accompanied by banjos and guitars would fit into that category. The string band music pre-Bluegrass would be what the label intends as well. There is always alt.country.oldtime on the BBS that can help you define it furthur.

Frank