To give you a hand:
< refers to the start of a word
[0-9A-ÿ.\-]{1,} (used twice) refers to a string of any length containing the specified range of characters
@ is an obvious requirement for an email address
([^13 -/\:-\@\\-`\{-¿]) says to tag whatever the first character is after the email address, which could be any punctuation character, a space, paragraph break, etc. (I got lazy and didn't bother excluding some non-punctuation characters)
\1 tells the replacement to use the first tagged Find expression.
I'll leave it to you to figure out the rest
