Support for Wammu and Gammu
Gammu and Wammu are free software projects. As such you can get some support from the community behind the project. The best place to start is usually the documentation, where many configuration issues and common situations are already covered.
If you are looking for list of supported phones, you can look into Gammu Phone Database. You can also share your experiences there, but if you had problems, please report bugs and do not write about problems only in phone database.
Community Support
If the documentation does not help, ask the community on the Gammu discussion forum. You can also use the forum to share ideas and experiences.
Reporting Bugs
Once you think you have hit a bug or want to file a feature request, please use a bug tracker to report them. Please be as descriptive as possible and include the information needed to reproduce the bug, such as debug logs. Security vulnerabilities in Gammu or python-gammu should be reported privately.
Commercial Support
Running some business application using Gammu, you might be interested in getting a better level of support. See how to contact the maintainer.