Formatting sidebar

Hi,

I am new to WordPress, just a couple of weeks working on it. I have managed to alter the default theme to suit a bit more my colour tastes, but there are a few things I cannot do, in spite of my intensive Google search.

One of them is chanting the colour of the sidebar links. They are blue, which is the default colour to the them I’m altering, but my preference being green, I’d like to change them.

I’ve been doing some googling and found the way to alter link colour, which should have solved my problem. However, the CSS lines supplied for change do not appear in my css style sheet !!! In fact there is no single line containing the word ‘link’ in the code 🙁

Can anybody help? Thanks!