The Glock 17 is a rather bulky piece. My first recommendation would be a good pancake-style holster, forward cant, worn just behind the strong-side hip (about 3:30 to 4:00 position).
The pancake designs anchor the holster in place fore-and-aft, and the smooth outer holster panel tends to reduce the profile of the holstered handgun better than many other designs.
This seems to be about the best solution for carrying the larger handguns.
Don't forget to use a good sturdy belt, which will support the weight and keep the holstered weapon locked in place without having to be tightened to an uncomfortable degree.
I offer several variations of the pancake style holsters, starting with the Model 1 Pancake @ $43.50, Model 1-SL Pancake with snap-loop belt attachment @ $53.50, and the Enhanced Pancake model @ $59.50.
Let me know if I can be of any help.