First of all, welcome to the forum - you have come to the right place for someone just starting out. I will try and give you some advice, or suggestions/ideas based on my years of both film and digital photography.
First - Canon and Nikon are not really cameras in the sense that they are a system of cameras, lenses, flashes, etc. that once you decide which "system" to follow you are probably committed for life, unless you have bags of money and can afford to switch every few years. Personally, I am a Canon guy, but don't let that influence you - my decision to go with Canon goes back to my days shooting film, you know - the dark ages of photography.

They (Canon and Nikon) are, however, felt to be the "leaders" in the digital world. although those who shoot Sony or Pentax might argue with me, nevertheless if you stick with either one, Canon or Nikon, you cannot go too far wrong. If I were you, I would start with a lower end digital, in Canon, something in the T3, T2i, T3i range, or Nikon, something in the D3100 or the D5100 - not a Nikon guy, so maybe Nikon guy would give you different ideas - don't know. If you are looking for second hand, then
B&H or
Adorama both have used equipment for sale, as well, try your local camera store or the likes of e-bay. The key is to go to a
camera store and compare them, try some of these units out in your hand to see how they feel and to test out the "ergonomics", i.e., are the buttons and dials laid out to your liking - have a look at this site and maybe you will get some more of your questions answered -
Canon EOS Beginners' FAQ
As far as editing software, there is Photoshop Elements - it has a lot of the features of its big brother Photoshop CS5, but costs about $100 compared to $700± for CS5. Alternatively, if you buy a camera new, it will come with post-processing software that should get you going for at least 6 months or a year (my opinion). There are also a number of "free" programs such as Gimp, Picassa and others - here's a list that will keep you going -
Free Photo Editors for Windows - Top Picks
For text books and other literature to get you going - too numerous to mention as a lot depends on the type of photography that you want to get into - so many of the books available are slanted towards a specific type of photogrpahy, e.g., wildlife, landscape, macro, portraits, weddings, etc. The real aspect that you need to understand are what could be called "elements of composition". To that end, two books by Bryan Peterson are worth looking at -
Understanding Exposure - 3rd Edition/Revised and Updated -
Amazon.com: Understanding Exposure, 3rd Edition: How to Shoot Great Photographs with Any Camera (9780817439392): Bryan Peterson: Books and
Learning to see Creatively, Revised Edition -
Amazon.com: Learning to See Creatively: Design, Color & Composition in Photography (Updated Edition) (9780817441814): Bryan Peterson: Books . Make sure that you get the latest editions of each book.
On the web, I would suggest Ron Bigelow's web sites. The first one is here,
Advanced Composition -- Part I and the link to the following ones are located at the bottom of each site - there are three altogether. Also, I would suggest you look at this one for additional links -
Photography Composition Articles Library . There are literally thousands of sites that cover some aspect of photography on the web - I am sure you knew that already - you just have to "Google away" until you find what you are looking for.
I trust that this will answer some of your questions - any more, post back and I am sure you will get a response.
Cheers,
WesternGuy