Grabbing referring keywords.....

Ok, I need either a tutorial or someone who has done so in the past to tell me how to do this.... I want to log and reference the key words used to find my site from referring search engines... like so: AltaVista: 211 3d studio max tutorials 81 body jewelry 43 body jewlery 32 3d studio max 21 bodyjewelry 11 3d studio tutorials I cannot relay on any log file, I have to create it myself.... (Long story here, don't ask...). I am very interested in learning this.... if anyone knows of a tutorial then please pass that on as well... Thanks much. Dallas K (Note: I know about using $HTTP_REFERER But how can I take that info and strip it, if that is what I need to do?)