I don't have any idea how to do leatherwork, and since I was starting on my Jedi costume less than 2 weeks before the convention I wasn't keen to try learning it. So I made my Jedi Utility Belt out of heavy, upholstery vinyl, which actually looks better in person than in these photos (enough so that more than one person asked me, first of all where I got my belt and secondly were surprised it was vinyl, and not leather). Both the wide belt and the narrow belt have card stock inside to stiffen them up so they are firm like leather would be. The card stock strip was simply strung through the vinyl tube, it isn't sewn in. I did that so I could replace the card stock as it wears out. The front buckle on the narrow belt is just for show, and the vertical loops either side of it are actually attached to the wide belt behind with upholstery thread (to keep the front from drooping).
Note: in the photo below the pouches hanging on the side are actually for a Russian field gun cleaning kit. I have yet to make my Jedi pouches, so the cleaning kit pouches (which are attached to each other) were borrowed just so I had something semi-appropriate hanging there. They will be replaced with a "Tall" pouch, a "small" pouch on the other side, and a "wide" pouch in the back.
Below you can see how I did the buckle at the back. The wide belt doesn't actually have a buckle, it slides through a loop and friction of vinyl-on-vinyl is what holds it in place until the narrow belt quick-connector is latched. Thus both belts can be adjusted for comfort (and future weight changes). The lower photo shows the back buckling undone.
I've encountered a problem with vinyl in the past regarding rivets where, as the vinyl stretches over time it gets loose around the rivets until they eventually tear out. I couldn't find rivets on short notice that would work anyway, so I decided to "fake" the belt rivets. I went to the hardware store an purchased ten aluminum "screw post assemblies" costing $0.49 each (eight longer ones and two short ones). I found eight washers in my kitchen junk drawer, then drilled out the holes so the screws would pass through, but the post couldn't. Below you can see close-up photos from both the front and back sides of these fake "guide rivets" for the narrow belt. I've also included a diagram to show you what these fake rivets are.
The two "rivets" either side of the buckle on the narrow belt are 1/4" Aluminum Screw Posts (below left) [Part # 86145] and the eight belt guide "rivets" are 1/2" Aluminum Screw Posts (below right) [Part # 86147] both made by Midwest Fastener and purchased as "Handi-Packs" at my local hardware store.
Lastly, a Jedi needs some way to hang the lightsaber from the Utility Belt. The two options are either to use a Covertec pager clip or a D-ring and hanger. The hangers used in the movies were just a single "picture hook," which doesn't look very nice. Since my lightsaber actually has some heft to it I wanted a sturdy hanger - something that wouldn't concentrate too much weight in one place on the belt, but spread the load a bit, and also something that would secure the lightsaber without my having to worry about it falling off when walking around at a convention. Below is the strip of aluminum I made into my D-ring hanger.