Thanks everyone, you have been a great help.
Earlier I posted my site here for a critique (www.workriver.com) and afterwords I changed the following: Logo, added mouseovers on important links, fixed the order of the ads by date posted. I know it still needs work on the colors and layout but im not really sure where to start there, or if i should just rebuild that from scratch.
Here is my question though: you guys mentioned that it was important for me to add a doctype. Is there a program (preferably free) that you know of that can go through my document and tell me which tags are outdated, and which ones are missing the < /> part? Most of it is all php echo "<html code>" so I would need something preferably that could ignore that and only fix the html/xhtml.
Im worried that if I add a doctype now, it would make it unreadable since its not currently up-to-date xhtml/html