The first 2 that come to mind are W.W. Grainger and McMaster Carr.    I like the paper versions because they are easier to browse.   I often have some idea of what I want and what it might be used for but don’t know the right name so pictures really help.   

I also like Thomas and Spectrum for chemicals and instruments.  

Finally, I am really impressed that a young engineer would ask this question.    I was taught that “The more parts you can buy from Grainger the better your design is likely to be.”  That is highly over simplified but still worth mentioning.  

One of the design projects of which I am most proud is a device to provide fresh water from a drinking fountain for dogs in a park.  Originally the concept was a dog level bowl with a float to maintain water level.  The big problem was how to keep it clean.

As a temporary measure we put up a stainless steel bowl on a chain.  People fill it from the fountain and put it down.  When they are through they can hang it up.  Even if they just leave it the next user empties it and refills it.   It has been “temporary” for about fifteen years and there is no reason to replace it.  It also seems to be vandal proof.   I’m not sure anyone has even tried to damage it.

Have a great career.

Tom  

Thomas J. Walz
Carbide Processors, Inc.
www.carbideprocessors.com

To Tom's list I might add J&L Industrial supply and Carr-Lane.  Also, see if you can get materials catalogs from your metals/plastics suppliers as they contain valuable information about the material properties.  If you have to occasionally deal with electronic components, Newark would be a good catalog to have.

I would hope you would have this reference already but if you do not, highly recommended would be Machinery's Handbook by Industrial Press.

Regards,

Grainger is a very good  example. They tend to sell the most popular items, so designing from their books will keep your costs down. They are contnually growing & adding new components, and they are one of the leaders in the industry. You may also look at MSC www1.mscdirect.com
Applied Industrial Technologies, Kaman, and Motion Industries are also big, nationwide didtribution chains, and ther are thousands of independants, they may offer better pricing, and service that is more tailored to your needs.

Russell Giuliano