If your project involves finding bricks to match the existing bricks used on, in or around your home -- maybe you're doing a room addition or making a repair -- a slight difference in brick colouration will be strikingly noticeable, even from far away. Matching bricks is an exacting science, requiring some footwork and searching, possibly even in other states, to find an exact match. As a last resort, you could try staining the bricks.
Find out the company that supplied the original bricks for your home. You can try contacting the builder, architect or previous owner for this information. The company that supplied the brick may still sell the same kind.
Use a quality digital camera to take pictures of the brick you need to match, if the company that supplied the brick no longer offers it or has gone out of business. Make sure the colour quality of the picture is accurate. When it comes to matching brick, you should always pay more attention to colour than texture because texture will only look different up close.
Check with brick distributors in your local area first. Show them the picture you took or ask if they will come out to your home. Don't let them talk you into a brick colour that doesn't match. Once the project is completed, mismatched bricks will stand out from any distance.
Mail the picture to brick distributors in a few different states if you have no luck locally. Those companies may have a brick that matches the colour of your existing bricks.
Contact local brick distributors about brick staining if you can't find the colour brick you're looking for. If you start with a brick of a similar texture, some companies can stain the bricks to match your existing ones. Be sure to test out this process on a few bricks before buying hundreds. This could add considerable cost to your project, so it should probably be viewed as a last resort.