Currently Being ModeratedJan 7, 2013 10:18 PM (in response to Ronniebel)
You can do it If your work email is set up as an account in Mail. In a New Message, the From field should have a drop down list of all your accounts. Simply select your work account.
Currently Being ModeratedJan 7, 2013 11:10 PM (in response to Ronniebel)
Joe's solution is right if you want to send from your work mail address as well as get the reply there.
If you want to send from your home address and request replies to your work address, set a Reply-To address. You can activate a Reply-To field in the header of new mail by selecting "Reply-To Address Field" in the pull-down menu near the headers:
The little button with three lines and a triangle is the pull-down menu I mean.