Bing is a great search engine and has a massive user base. Not as much as Google but search engines like Bing and Yahoo should not be overlooked. The Bing search engines has bots that crawl the web and index pages every day. This is a generally slow process for Bing as they have a slower algorithm than big G's. It may take years for a website to get every page indexed. Here is the standard way I use to kickstart the Bing bots.
STEP 1: OPEN A BING WEBMASTER TOOLS ACCOUNT
STEP 2: ADD & VERIFY YOUR WEBSITE
STEP 3: CREATE AND UPLOAD YOUR SITEMAPS
STEP 4: CREATE A SEARCH OPTIMIZATION PLAN
This really should done by every webmaster for every site. Bing and Yahoo need a little encouragement to keep up with Google. I prefer to let Google follow the links in my site so every new page is indexed from a relevant text link.
Hope this helps.