Welcome to the Infusionsoft Community, Keith! I hope you'll enjoy and participate with the many great folks and resources available here.
Before I get into my answers below, I want to let you know that the Infusionsoft app will change significantly near the end of the month; so don't get *too* used to the procedures below.
I would consider creating additional Contact Groups that truly target your customers. That is, narrow down to their interests and their sources.
Also do the same thing with your affiliates -- segment them by performance, types of affiliate marketing or whatnot.
When regard to the Search issue that you mention, it is cumulative in nature. That is, it lets you continually fine-tune and narrow searches down. In this case, be sure to "Reset" the search if it is not functioning right. If you still observe a limited number of results than expected; Infusionsoft may still be processing your import and you can check on that through the Reporting/Scheduled Actions interface.
Hope this helps. Let us know how it works out. In any case, our support staff is available anytime to help you better understand and carry out the goals you need at first.
~Joe