Marketing an information product is very much like selling an affiliate product. There are some differences as obviously selling your own product does require some additional things such as sales copy and special image creation.
To cover the basics though you want to create a wordpress blog centered completely around the information product you are selling, on this blog you are going to have an opt-in to build a email list. As it is always suggested offer your visitors something in exchange for their email address.
Your blog will not be a "sales blog" but an information source instead which leads to your sales page. I highly suggest building your sales page on a sub-domain of the domain and use keywords in that sub-domain. You need to provide high quality fresh content on this blog constantly (ie: schedule post 1 per day) for search engines to spider.
Providing scheduled content that will post for a good 60 days would be perfect. This will free your time up to actually do marketing on the site. You should have at minimum All-In-One-SEO-Plugin and the Google XML Sitemap plugins installed.
On your mail list you could offer mini ebooks or reports for free then up-sell that list to the advanced version or sell the ebook itself as a whole. I think this part really depends upon what you feel is best for your business, there is no set in stone method.
Marketing your blog you would do through article marketing and using the methods taught on this very forum. You would focus on social media by creating some accounts for this blog at digg, facebook, multiply, livejournal, and/or other sites you already are familiar with. You want to make sure that you do bookmarks on those scheduled post, so everyday a post is made try to get at random from 35 to 50 bookmarks.
Make sure you do your bookmarking and social media post randomly. Maybe you want to bookmark post #2 today and syndicate post #1 then the next day bookmark post #1 and syndicate post #3 and etc. Because you setup your blog with a scheduled 60 days of post you will have the time to spend randomly doing your social media and bookmarks.