Well, let me start by saying that there is one thing I liked about your webiste - it looks exactly the same in every browser I opened it in (Netscape 9, Opera 9, IE 6, IE 7, Firefox 2, and Maxthon 2 - it even worked in Lynx). Sadly, that was pretty much the only thing I liked.
To start with, you have to many ads, and they are in all the wrong places. The advertisements on the very top of your site push everything else down and ruin the entire look by themselves. The skyscraper ads should be placed alongside the content, not inline with it - they push your content apart and make it extremely annoying to read. The list of link ads under your header are easily confused with navigation links, and stretch outside of your template. And the billion ads, buttons, and other nonsense in the footer are never going to be looked at by anyone in their right mind, because they don't fit in - they look like ads. In some pages, you have two side-by-side banner ads along the bottom, which just looks silly (though it's far better than the in-content skyscrapers).
To pack that whole paragraph into one sentence - your ad placement and choice is awful, and no one is going to stay on your website for more than a quarter of a second unless you fix it.
Secondly, your site search is broken. (Not the Google Search box on your main page, the search bar in for sidebar on all the others.) I get an error message every time a search, and I never get results. Sometimes I don't even get an error message from the search, I get a full blown 404 page. That's not good.
Your font choices don't match up - you have giant orange links on your main page that are larger than your section headers, making them look like big ugly section headers themselves. It's very confusing. Also, the smaller orange links are a little bit hard to read against the background colour, and the black font used to label the fields in your contact forum doesn't match the white font used everywhere else on your site.
The clocks on your resources page don't match your overall look, and simply serve to push the page content down even more without being useful in any way. Similarly, the date in the navigation bar is useless and looks out of place. The same goes for the rather ugly video box on your main page.
Your code isn't valid - there's a whopping 117 errors. You didn't specify a document type either.
Ok - now that I've torn your site to bits, let me offer some advice:
You site, at it's core, has hope. To demonstrate, take a look at this screenshot I took of your "Forensics" page with an AdBlock enabled and scrolled down so as not to show the "Post free classified ads" link:
http://alternative-internet.com/webmasterstuff/sectionc/philapcrepair.png
That looks good. Actually, that looks very good - I still might alter the orange link colour just a little, and I'd remove the date from the top of the navigation bar, but even so, that's a good page. It's clean, easy to navigate, has an easy to find search bar - even handy buttons for sharing or printing the page.
If you really can't lose the ads, that's fine too - you just need to cut back on them and place them better. For example:
http://alternative-internet.com/webmasterstuff/sectionc/philapcrepairads.png
That's another screenshot of the same page, but with ads placed in it the way the should be - noticeable, but not ugly or in the way.
Really, there isn't a whole lot you need to do to get your site from where it is now to there either.
Start by removing all of the ads - period. Even if you're going to put some back, cut all of them out first. Also cut out your search box (since it doesn't work), those silly clocks, the video box on the main page, and the date in your navigation bar.
Then re-validate your page so you can determine which errors are left, and fix them.
Once they are fixed, you can start putting ads back, but keep them in the template (i.e. not outside of your rather nifty design), and out of the content's way. Placing skyscrapers or boxes to the right of, or banners below your content are best. If you need to, you can place banners above your content, but keep them below your header. And remember - less is more. Not only do fewer ads looks better, but if you have fewer ads, visitors are more likely to click them (and to stay on your site instead of fleeing).
Once you've got all that done, you can worry about fixing your search. I noticed you had both a Google search on the main page, and an internal search on your other pages - don't do that. You only need one search, so pick either internal or Google powered. Also, if you go Google, keep in mind that there are different versions of Google's custom search box that let you tweak it - for example, remove the "search the web" link so it only searches your site. After all, visitors can search the web from Google itself - you want them to stay on your site.
Lastly, do the minor touch ups - such as getting the input box labels on your forums to match the rest of the text on your site. Also, consider removing or altering the "Bookmark this Page" star, as it currently only works in IE browsers (though that isn't too necessary).
I hope all of that helps, and I'm sorry for being so harsh to start out. As those screenshots show, you've got a really good site, you just need to let it show itself more!
Edit: it seems Breeze beat me to it. Darn. That's what you get when you write so much. He did, however, catch something I didn't - the tables. If at all possible, you should switch to divs. CSS is much easier to use, and most web designers/developers shun tables these days, so getting away from them is in your best interests. If you follow my recommendations above, I'd suggest converting your look from tables to divs after you've removed all the ads but before you start putting any back - and make sure you validate your div-based layout.
-Patrick J. B. Simmons | @hobbramble
"If I could give you one piece of advice to remember for the rest of your life, it would be this: when Patrick tells you to do something, do the opposite." - Nolan Ladewski