If you ever get to/through Denver, go visit the Capt Jeppesen archive. There is a facsimile of his 'Little Black Book'. I'm sure if you ctc the Jepp office in the ACT on 261 202 999 they'll let you have (or loan you) a copy of the Capt. Jepp story on vid or DVD. This does give a great insight to the early days in the US.
Let me know how you get on