The filtering of link results by google is mostly about the page rank of the linking pages. Internal links are just as good as external links for building both link reputation and Page Rank.

To see if your pages are included in the google index, type the URL of the page into the Google search box and see if it recognizes it as a URL in its index. Also check your server logs to see what pages googlebot has visited.

All of your pages count, whether they are shown in the 'backlinks' query or not. Your internal pages will show if they are high enough in page rank. To increase the Page Rank of your pages, build more pages -- which is the actual source of Page Rank -- and link all your pages together to conserve and concentrate Page Rank within your site (see my Dynamic Linking ebook included in Michael Campbell's Revenge of the Mininet package at http://www.optitext.com/revenge). Also, the OptiSpider product, included as a demo with OptiLink, shows the inbound and outbound link counts for all the pages on your site, very useful in optimizing where page rank gets distributed as well as being a live test of the spiderability of your internal pages.