The only problem with specifying link text colors in a tag other than the <a> tag is that the underline in most browsers will be displayed as the color specified for the link, but the text itself will be the color specified in the other tag, for the example above, the color for the <p> tag.
I've found this to be the best way.
INSIDE A STYLE SHEET
IN THE HTML CODE
<a href="">Blue colored link</a>
<a href="" class="differentLink">Gray colored link text</a>
You could also specify different properties for the various states that a link can be in: unvisited, visited, active, and when the mouse is hovering over it.
If you already know about that, forgive the review.
A great site for CSS is http://www.w3schools.com/. It has a complete reference for CSS 1, 2, and 3.