Btw every should check out nofilmschool.com. I've learned A TON of shit from that site. Also they offer (the free) DSLR cinematography guide which might just be what the OP (and maybe others as well) needs. (It's a bit outdated but truth be told on the cheaper end of things it still applies and if you follow the advice given in the book you might get some great used gear for cheap.)
Also check out the YouTube-Channels SamandNiko (from CorridorDigital) and FilmRiot. They really teach a lot of very useful stuff over there. Here's a piece about lenses:
DigitalRev TV also has a lot of helpful reviews.
If you buy Canon always aim for the ones with the red ring. Yes, they are expensive but all the others are just toys that don't produce professional quality and have no re-sale value. If they are too expensive you can always rent them for 30-50 bucks a day. Might be a good idea to do some experimenting with your stock lens and then get something better for the actual shoot. These are the ones you'll most likely need (in this order) for music video and interview situations: 24-105mm, 50mm, 70-200mm.
Don't forget about lights btw. Check out Filmriot (mentioned above) to learn how to set them up. They have great tutorials on how to get the job done for cheap.
If you are just starting out and don't know how to set the parameters of your camera check this out:
http://www.canonoutsideofauto.ca/play/ It's a great learning tool that doesn't even require you to have an actual camera.
(General rule: Keep the ISO below or equal to 800 and adjust the other parameters from there - they all affect each other, just like an EQ on an amp.)
If that info doesn't get you started nothing will. That's really all you need to know.
