I have sent mails to many bus-fans all over the world. It helped me identify a lot of them, sometimes they don't just care and do not reply or reply very short.
Look at the make CASA and MESA...that person was very helpful...

http://www.imcdb.org/vehicle_47071-Casa-Delfin.html
http://www.imcdb.org/vehicle_47072-Masa-S-500.html

Also some Italian buses I have found that way.
It's very nice to find people who now a lot about buses and most of the time they are very helpful.