Besides Amazon, B&H Photo http://www.bhphotovideo.com/ and Adorama http://www.adorama.com/ are two big, reputable photography stores with large online presence.
Congrats on Canon find. Loving your Kit
You'll probably find you'll stick with Canon from here on out (not a bad thing at all), most stay with the camera there lens work on.
If your adventurous, and considring hacked firmware, there's custom firmware for Canon camera's. Beware, you can always brick your camera.
http://magiclantern....n_Firmware_Wiki - have to way the pro's / con's vs potential risk.
If your looking for a free / light room open source alternative - check out Light Zone
http://lightzoneproject.org/ - Use to be commercial software, went bankrupt, and the code was open sourced.
Adobe Light room is still a good choice, but I'm still using V2, 1st to support 64bit, DNG format, and no internet activation (I did buy a copy).
If the raw isn't supported, you can use adobe free dng converter, converted to older dng, then open in Lightroom 2.
If you go Lightroom route, check out Nathaniel Coalson books on Lightroom.
If your looking for 100+ good tutorial video's, check out https://www.youtube....er/photoexposed - from basics, to advanced.