This bracelet is designed in SolidWorks and produced with Shapeways,
It's easy and cheap!

The bracelet is also available on Shapeways for 9,24.
http://www.shapeways.com/model/1151624/simple-black-bracelet.html?li=my-models
However, it's always more fun to design ityourself. So here are the easy steps to take in order to design a bracelet!

Step 1: Design the Charm

First of all, design the charm.
Determine the maximal measurements. When designing the inner wires, think of the minimal wall thickness of the material you want to use. Between 1 or 2 mm is oké.

Extrude the sketch made in Solidworks for 1 or 2 mm.

Step 2: Adding the Ring

Sketch a ring in the top plane. Extrude it.

Step 3: Bending

Add fillets to the charm.

Use the feature 'flex' in SolidWorks (insert>features>flex) to bend the charm a bit. This way, the bracelet will be more round.

Step 4: Design the Lock, Part One

For the lock, I used the letters D and L. The L is supposed to go in the D. The long strip of the L will make sure the bracelet is locked.

Instead of D and L, you could also make a normal ring and rod.
To make the L be able to go through the D, there should be a small chain attached to the letter (same for the ring and rod).

For the letter L, make a sketch and use the text option. Size of the L can be determined by clicking the 'font' button. Under 'Heights' chose units and the size in mm you want the letter to be. The L should be around 1,5 - 2 times as big as the D. In the picture of the printed version this is not the case. The lock doesn't work their, so I changed the measurements in the SolidWorks files.

Cut the horizental line of the L shorter with an extruded cut. The L should fit through the D, so i cut the horizental line in half.

The chain can be made in the same files. Make a plane halfway the L. Sketch, extrude en fillet some rings.Make another transverse plane and make the half ring and the ring connecting the other rings.

Or you could just make the half ring connected to the L. Then make a ring in another file and connect the L with multiple rings in an assembly.

Step 5: Make the Locket Part Two

Make a new file and sketch the letter D (or just a normal ring).
Attach a half ring on it.

Extrude the letter and the ring. You can use fillets to make the ring nicer.

Step 6: Assemble the Parts!

It's time to make the assembly.
Measure your wrist and decide how long the bracelet should be and how much charms are needed. I used 8 charms.

Load the charms and locket parts in an assembly. Move and rotate them around until they form a nice bracelet. Make sure none of the parts interfere with each other.

Save the file as a .stl file.

Step 7: Upload on Shapeways

Log in on Shapeways or make an account.
Click 'make and sell' and upload your .stl file.

Wait until it is uploaded. You will receive an email when your model is ready to be printed, this can take a few minutes.
You will be able to view your model.

Select your material. Each material has its own minimal wall thickness, make sure the chosen material has a lower minimal wall thickness than the smallest wires/walls in your model.

Order the product, pay, and wait. In two to three weeks you will have your own designed bracelet!