Hi Larry and Welcome to the Forum!
What information EXACTLY are you looking for?
Motorhomes are not like automobiles when it comes to manuals. The Allegro Owners Manual was likely little more than some generic information on the coach and camping tips. There would be individual manuals for the chassis and all other systems (fridge, furnace, water heater, etc.) each with a separate manual. Most of those manuals can be obtained off the Internet (in PDF form) from the individual manufacturer of each system.
This web link should get you started on finding a few manuals:
Service Documents and Manuals