Step 1) Look up the Homeschool Laws for IN
http://homeschooling.gomilpitas.com/laws/blIN.htm Just at a cursory glance, it seems pretty easy. Looks like just attendance records. ((Some states require academic yearly plans, attendance, portfolios (with reviews), and/or yearly testing... plus various hoops to jump through in regards to teacher qualifications, curricula, and a whole host of admin stuff)) Getting in touch with people in IN will be the MOST useful thing in regards to laws and how to be in compliance. Which brings us to:
Step 2) Research & Networking & Support. http://groups.yahoo.com/ has homeschool message boards from every avenue you can possibly think of. Religious, Secular, Special Needs, Gifted, 2e, Local, Philosophical -as in what philosophy or curriculum you use-, age group, college bound, you name it. Many/most of us on are several boards there, just because there are so many amazing resources to be found. I think right now I'm on around 10, from a local field trip group with only a few hundred members to some large multinational boards with 10,000s . I WISH I had known about them when I was new to HS'ing. If you're secular http://groups.yahoo.com/group/secular_homeschoolers/ is an extremely active and very helpful board.
Step 3) Curriculum
You have a GAZILLION choices out there. You also have TIME. You can even take a couple of months to recoup, plan, and breathe. The average yearly PS curriculum can be completed in 3-4 months by an average student only working 2-3 hours a day.
Fully 1/2 of the curriculum options out there are free to mostly free. You also (I would assume) have all of her current school books, which are a good place to start from. As far as curricula goes, k12 is fairly decent/okay, and as long as you're in one of their VA's, they ARE free. Only though, as you've found, they have certain registration "windows". IT IS NOT WORTH THE MONEY to pay for them out of pocket, unless money isn't a concern... since you can get far better for far far less.
Some places to check out curricula / philosophies:
http://www.homeschooldiner.com/
http://homeschooling.gomilpitas.com/
http://www.homeschoolbuyersco-op.org/
here are also some of our (totally biased, and eclectic ;) favs:
http://simplycharlottemason.com/basics/what-is-the-charlo... (free with a library card)
http://simplycharlottemason.com/basics/started/charlotte-...
(free with a library card)
http://www.discoveryeducation.com/ (see if you can get it free through your school... otw it's about $100 a year, and the most expensive thing on here)
http://www.noeoscience.com/catalog.html ($20 per unit, christian co, but secular science)
http://www.freemontessori.org/ (free ... as are many other amaaaaazing montessori resources if you look around... and yup... montessori goes all the way to high school)
http://www.singaporemath.com/ ($35 per unit, typ 2 a year... general math)
http://www.borenson.com/ ($35 ... algebra)
There are about 1000 ways to homeschool "correctly". AKA, in my opinion, to meet or exceed the education gained from a more traditional school. It can be VERY overwhelming, and like anything it has it's own lingo, which can take a bit to wade through. So my biggest piece of advice: Breathe, & take your time. Get well, don't rush, and don't spend a ton of money on anything up front. You have time.
:) :) :)