Vuts, are you talking about the mixdown stage or the mastering stage?
When you refer to maximizing the tracks in the mix, that leads me to believe it's the mixdown stage. If that's the case, you should just try to get a good, balanced mix and not worry about the loudness yet.
For a mixdown you should typically keep your peaks around -6db or lower, to be safe. And by all means don't go crazy with compression on the master buss during mixdown. Just a low ratio and a few db of peak reduction to solidify the mix, if necessary.
The loudness comes in the mastering stage, and for that you need a decent (hardware or software) mastering compressor/limiter and eq at the very least.
But if you don't really know what you're doing on the mastering side, you're never gonna get it as "loud" as a major commercial release. I'm not saying don't try. Try everything, but maybe lower your expectations a bit on the loudness part when referencing against recordings you like.
Turn down your reference material and focus more on comparing how things sound and make changes based on eq, panning, compression on single instruments, etc. Improving in those areas will really help you get more volume in the end.
Not knowing anything about your project or setup, I'd say just try to make it sound as balanced as possible on a few different systems within your reach -- reference monitors, car, home stereo, computer speakers, etc. Find the loudest point at which it still sounds good and stop.
Like Asmus said, people can just turn up the volume!
