[otrs] Integration with OTRS.

Good day! First of all sorry if this list isn't the correct place for such a question. I'm have to write som kind of web-interface for users to pass requests to OTRS and see results of request processing. First (passing requests to OTRS) can be done simple by sending an e-mail message as far as I know, but how can I get ticket status? Or may be I can define some kind of callback, that will be called every time ticket is processed? I looked through OTRS documentation (may be not so attentively as I should) and had no luck.. :/ Any links, comments etc. will be highly appreciated. Thanks in advance. -- Regards, Eugene Kosov.