You have far, far more intestinal fortitude than I do to go into that business. (It involves marginal work and low margins. Yikes -- software sounds so much better.)<p>I'd say "both". My reasoning is that you can use the B2C customers as the kindling to light the B2B fire -- they're cheap, easy to service, and numerous. Get them to do your marketing for you. (You can use your existing technology to quickly roll out linkbait mini-projects: web form + visual design + PDFification + a letter physically delivered to grandma = instant remarkable content. You can launch one of these a week: Send A Solider A Valentine, for example. That is probably a little late but you get the general tenor of the sort of emotional buttons I'd suggest you push.)<p>This gives you something to do while waiting for the phone to ring on the B2B deals, and will help you with SEO. Why focus on B2B over the long term? Well, it allows you to have much more predictable revenue, and having a lifetime customer value which could buy a pizza is very helpful once you start think of incremental-cost marketing options like, say, AdWords.<p>Mind if I give you the same advice I gave cperciva? Thirty minutes on that home page will double your sales. Heck, if you're in a hurry, you can do it in two: put a BIG OBVIOUS BUTTON on it. I don't know, 10 kilopixels of big. Maybe bigger.<p>If you have graphical talent, something I lack, I'd collapse the entire sales pitch into an illustrated:<p>1) Put in address
2) Type letter (We take PDFs, too!)
3) Pay money and it gets mailed<p>I'd put the API & login links in the top corner and the bottom of your textual description, or somewhere similarly discrete. (The audience for those is very different than the audience who you want converting within 90 seconds of landing on your site.)