I think if you want to learn how other people do things and compare mixes and all that...go hang out in the MP3 Clinic forum, or get involved in the Mix This! forum here on HR.
Yes, there are so many online resources to learn about recording, mixing, mastering, sampling, arranging...it's amazing. Ever heard of YouTube? Haha. And if you've got the cash, you can pay for all sorts of master classes online at various levels of pricing and experience...pretty sure Masterclass.com has a six-hour course on electronic music production from Deadmau5 for like $90. Just one example. And that's $15 a freakin' hour. That's what Amazon pays their employees, and you can pay that much for a class from a guy like Deadmau5. It's crazy.
That being said, I am not sure if anyone suggested this trick or not, but most mix engineers I know from many different levels in the industry, guys like Mike McCarthy (Spoon, Heartless Bastards, Leann Womack) and Johnny K (Disturbed, Finger Eleven, Megadeth, Plain White T's) and Manny Sanchez (Fallout Boy, Psy) all use at least two, if not three compressors on most vocals, especially lead vocals and lead harmonies. That would REALLY make it a lot easier to even out the final mix levels on your original track. They typically set the first compressor to a hard and fast setting to catch all the plosive sounds that peak out the meters, like 10:1 ratio with fast attack/release settings but only grabbing maybe 3-5 db of the signal...then the second one is set to smooth things out a bit, like 3:1, medium attack, slightly slower than medium release, and it should be consistently grabbing 7-10db. I prefer a Distressor on most male rock vocals. (This trick is also assuming the vocals were tracked through a compressor and touched just a bit by it on the way in. If not, then the first compressor assumes that function and the second one becomes the first one as described above and so forth.)
For the record, I wouldn't worry about the LRA or whatever that is; the difference between the quietest and loudest parts are almost irrelevant these days, unless you plan on going to terrestrial radio with it (ever heard "Today" by the Smashing Pumpkins on FM radio? It's hilarious how much louder the VERY quiet guitar intro becomes next to the HUGE entry of the full band as it is on the recording...not sure why Virgin didn't send out a single version mastered specifically for radio...they did that for my band when I was signed to them about ten years back). I would mainly consider the average and the peaks and try to smooth out the difference between the two a bit. But only a bit. Personally, I'm not a fan of how a lot of modern albums are mastered, as if having even a little *true* dynamic range would cause cancer or something. I think it's the mistaken human perception that louder is better. Balls, I say!