My favorite websites:
the How to Adopt section at:
www.nacac.org/
(if I were you I would just print out that whole section. it's written excellently.)
the Meet the Children section at:
www.adoptuskids.org/
(the majority of the kids there are over 5)
and also you should probably see:
www.nwae.org
(they have had more younger children added there just recently)
... there are many more... do a search!
You do need to be somewhat stable in that you need to be able to prove you can support a child on your budget, but a certain amount of debt and not being a homeowner should NOT be seen as problems at all, don't let that keep you from starting the process when you're ready.
Keep researching, both online and at the bookstore, so you can decide what type of adoption is right for you!
Good luck.