Online deal forums are platforms where participants share information about sales promotions, but the high volume and uncertainty of messages can make it difficult to identify useful deals. This study developed an intelligent deal alert service that mines these forums to help users find valuable deals. The service periodically crawls deal forums, collects new posts and responses, and evaluates them using probabilistic text classification. Users receive notifications of potentially useful deals via email or can browse them online. Preliminary evaluations show the service effectively reduces the time needed to find useful deals.