Here's a great example of free, value-laden content that also seeks to sell you something. This is a concept that I'm often harping on during our discussions about "free" over at Make and Meaning. I think Hoefler & Frere Jones strikes the balance between salesmanship and free, valuable content very well here. The lesson provides good advice about combining typefaces. The lesson also uses typefaces from the Hoefler & Frere Jones foundry as examples. Links are provided to pages where you can buy said typefaces, but nowhere is there a hard sell to be seen. They just show how brilliantly their typefaces can be combined, give you a place to buy them if you want, and let it go at that. Nice.