I raise my hand, I have attended a retreat held by the staff at Glorian: www.gnosticteachings.org the retreat was great, schedule included meditation and pranayama sessions, mantras/vocalizations and detailed lectures about the spiritual path, consciousness, religion, enlightenment, occultism, esotericism etc etc. I found this group to be safe and a take it or leave it (its up to you) attitude, they give you the practices and information, then it is up to you whether you decide to take it any further after the retreat is over. In my opinion, what they teach is a robust and complete system of spiritual development.
If you are interested to know more about what this group teaches, I highly recommend you visit their sister site which is www.gnosticradio.org where you can download lectures about various subjects, each week they do a live lecture where you can join in an online chat to ask questions at the end, I believe the lectures can be heard live or streaming through iTunes as well, otherwise the site above contains a lot of those audio lectures transcribed into written format for easy reading, complete with diagrams and a forum, etc.
If you are interested to know more about what this group teaches, I highly recommend you visit their sister site which is www.gnosticradio.org where you can download lectures about various subjects, each week they do a live lecture where you can join in an online chat to ask questions at the end, I believe the lectures can be heard live or streaming through iTunes as well, otherwise the site above contains a lot of those audio lectures transcribed into written format for easy reading, complete with diagrams and a forum, etc.