The CONCATENATE formula allows one to combine text from multiple cells into a single cell. The CONCATENATE formula is in the Text category in the Insert Function dialog box.
To add a blank character between words, type a space between quotation marks. This adds a blank character between the separated text. Whatever is between the quotes, be it a space, text or characters, it will show up in the concatenation.
So, if you were trying to create an email address at Dartmouth College, the formula would be:
Which would yield: Mickey.Mouse@dartmouth.edu