There are several entities that offer commercial support for YAWL-related work:
Acclario BPM (Scandinavia)
Acclario (Brisbane, QLD, Australia)
YAWL consulting
The YAWL Foundation is a non-profit organisation that acts as custodian of all IP related to YAWL and its support environment.
Take 10 minutes of your time to answer the YAWL questionnaire.