EDIT: Just to answer that question about finding people near you, check out the "Regional Zones" section of this very forum (it's called something like that). Find the thread relating to your area and post there. Also, theres a google earth addon who's name escapes me (Global Smasher something) that can be used to locate smashers all over the world. If someone else can elaborate on this tool, it sounds like a good bet (if it works the way I think it does).
The advanced techs in Smash have to be 100% instinct. When you're trying to aerial an opponent, you can't think "shorthop, aerial, fastfall, L-cancel", you have to think "shffl".
Acualy, scratch that. You shouldn't think at all about it.
It takes several months for the average new player to learn all these techs well enough to be fluently used in combat.
Here, try this. Let's assume for the sake of arguement that you want to play Falco (I personally play Falco, so it's easier for him to be the example). Go into training mode or an endless melee one time in your spare time. Practice, say, the SHL (shorthop laser, a Falco-specific technique. All characters have something character-specific you'll need to learn to do). Once you can do it more or less, ask your brother to play with you. Pick Falco, and use a rediculously excessive amount of SHL against him. Tack on at least 75% a stock on lasers alone against him.
Once you are proficient with your laser, go into training again and learn something else, like say, shffling. Once you can do that somewhat, play against you brother and use nothing but shffled aerials at him. Dosn't matter which aerial, just spam shffled stuff in his face. Take whole stocks with shffls and SHL (which you should now be able to approach and cover your retreats with as well).
And so on and so forth, until your tech skill is proficient. Yes, this is a long process. Yes, it is tedious. Yes, it is **** well worth it. As already mentioned by other members, finding some players who are better then you to teach you this stuff and play against (you can meet many, many people at tournaments) will accelerate the learning process ten-fold.
But most importantly, don't give up! It's far from impossible to learn the advanced techs of Smash.