Hardware is like jewelry for a piece of furniture.  The right hardware emphasizes the style of a furniture piece and helps tie the piece into the design of a room.
Here are a few tips for picking out hardware:

Sourcing
A few of my favorite places to look for hardware are:

Local
I try to purchase hardware locally when I can:
Lee Valley Hardware has a large selection and local pickup (if desired):  

Home Depot and Lowe's also have a good selection of in stock and special order handles.  My favorite midcentury inspired finger pulls and   bar pulls

Etsy is a great place to shop for unique, vintage and modern handles.
 

Online​
Etsy offers a wide variety of unique pulls.  If you're looking for hardware that is bold, unique or exceptional quality, Etsy is a great site to shop!
 

Amazon has  great prices on hardware, though the quality varies widely.  Checking product ratings and reviews is a must before ordering pulls or knobs on Amazon.

 

Sizing
The simplest way to update drawer pulls are to order new handles with the same center-to-center (c- distance as the original pulls.  You can do this by measuring from the center of one hole to the center of the next hole on the drawer. Some center to center distances that are commonly manufactured today:

• 2½" (64 mm)

• 3" (76 mm)

• 3½" (89 mm)

• 4" (102 mm)

• 5" (127 mm)

• 8" (203 mm)

Sometimes filling the old holes and re-drilling for a new hole distance is necessary.  Recently, another option has entered the market: adjustable pulls.  Franklin Adjusta-Pulls are high quality and come in a range of styles and sizes.  
For great tips on choosing new hardware with pleasing scale, Wayfair has some great suggestions.

 

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