Where can I learn more about business to business advertising on ...
depends on what you are advertising and what kinds of businesses are your specified target market.
Yahoo bought up a campany called overture, that was responsible for virtually all internet portal search results for businesses.
Google also has a program called adsense that delivers highly targeted traffic to your site
Depending on your products/services, it may be beneficial to paste an ad on the intetnet usenet sites, bulitin boards, and/or classifieds sites