I own a Glock 36, Their sub-compact .45 acp design and though I've never heard the term "closed carry" I'm going to assume that you mean concealed carry. There are some good holsters for either mode of carry. For concealed carry, DeSantis makes an IWB holster called the Sof-Tuc. It is designed to allow you to tuck in your shirt and also has an adjustable cant. Being able to adjust it to cant your pistol forward reduces printing a little, but keep in mind this is one of the largest "sub-compact" designed I know and it may or may not be to your liking for concealed carry in this fashion. For open carry, INHO there just is nothing better than a Blackhawk SERPA Level II both for retention and ease of carry. with the paddle you can take the holster on and off without undoing your belt.
The same holsters are available for the larger Glock 30, the double stack .45 ACP variant, but again, this is a large pistol to carry IWB as it is even wider at the grip than the Glock 36, it's single stack counterpart. For the Glock 36, the but plate design isn't the best, but on the plus side, Pierce makes great after market replacements that are pretty cheep. These Butt plates come in +1 and +0, and both make the butt plate a more seamless extension of the grip. To see what I'm talking about, see THIS THREAD talking about how the G36 factory butt plate caused me to get large blood blisters on my pinky finger. I wasn't worried about capacity so much so I went with the +0 replacements, and this took care of my problem perfectly.
Another thing to consider is that the Glock 36 is an "odd ball." It's magazines do not interchange with any other .45 acp Glock magazine. They are single stack, however they require double stack magazine pouches. Think of it as if they modified a double stack magazine to only accept rounds in a single stack configuration. They are a bitt bulky considering that they only carry 6 rounds (7 if you go with the +1 butt plate).