Landing Pages

We have yet to figure out how to master landing pages or getting visitors to the correct or most relevant pages when searching the SE's. We understand the weight of a page but we have traffic that comes in off terms but the more relevant and specific page doesnt necessarily show up in the SERP's. Our products page seems to have a lot of weight b/c it shows up many times in the SERP's as long as the term people are searching for is present in the description for the products page. Problem is, its not the most specific page and there are pages that have exact terms to match what visitors are searching for.

The pages have matching page titles (browser and h1), h1 tags and descriptions with the targeted keyterms within. We have built links to some of the interior pages. It appears that we need to do more link building but using directories only allows 1 link or allows you to link to the home page and not interior pages. We have submitted a sitemap to the major search engines, have the keywords in the URL's and have content on the site that links to products with the product name in the anchor text.

Questions are, what else can we do to display more relevant landing pages in the SERP's? What other ways are there to get deeper links? Any other suggestions that can help to get the more relevant pages in the SERP's? If building links is the prevalent, what are successful techniques? What have you done that has proven successful with your landing pages?

We feel this is a big factor to our conversions as people are landing on the main category page and do not want to thumb around and find what they are looking for. For the few deeper pages that show up in the SERP's, people only visit the 1st page and then leave. We experimented with having links to sub-categories with descriptions, all of the versions of the product laid out, pictures of the product with a description and cant seem to figure out the right combination.