There are many ways of doing it and I can keep writing for hours about it but I’m using cell phone for now so annoying to type.
For firefox use adblock, besides for blocking all ads it lets you block any picture or you might want to block the whole directory. site.com/promo/july.jpg then I suggest blocking promo dir not just july.jpg image.
For internet explorer use IE7pro.
Generally when going to ebay or any clothing store online search google and for a specific category like ebay computers an go to that specific category. Or start typing in your browser and go to suggested previously visited page instead of front page.