[RiskyFlame]

The main method I use is the Advanced Search option.

getDare Forums > Search > Advanced Search > Search by User Name
Type the user's name in the box and if you're not sure, uncheck the Exact name box. When you click on the Search Now button, you'll get all the posts of this user. Then don't click on one of his posts, but instead, on his name in the blue header of the list with results.

There's only one drawback when using this method to search other users. You can only find them if they posted at least once in the forums, regardless of whether the post counts towards their total posts or not.