You'll find a telephone no. on your C/Card receipt. Also, you can contact them via email. Check the top of the LW support page "I need help with LimeWire PRO": http://www.limewire.com/english/content/support.shtml

Since you've provided no details of your OSX & connection set up we can't help you until you do.

It would also be highly worth your effort looking at the Stickies at the top of this & the General OSX section of the forum.