Well, the waters are deep in the Glidecam vs. Steadicam vs. X, Y and Z discussion, almost as deep as cameras, adapters and microphones... Except that (even to a worse degree than the adapter market) there are really not a lot of hard and fast answers.
Anyway, for those with a Glidecam and having trouble, or those considering the option of a Glidecam, here are few links on how-to, personal experiences, and so on.
Here is one man's experience with the GLIDECAM 2000 and the CANON XHA1. It includes videos of his stages of learning. And here are a few pointers from the DVXuser FORUM on the XHA1 with the Glidecam 4000.
A tutorial video on balancing it with the XL2:
How to balance a Canon XL2 on a glidecam
And I am generally not one to promote corporate sites, but this VIDEO from the Glidecam site goes over the balancing mechanisms to a degree.