Hey Nadeem!
Sounds like you're the perfect candidate for a cool little NANO!

This is a marine tank that is less than 120L. The same concepts apply but you can manage things a little differently. These little tanks are a lot more common in the states - I highly recommend you visit
Nano-Reef.com - The source for nano reef aquarium information to see some of the tanks and read the articles in their library. Easy starter info!

But this is always my first stop for info - great forum and lots of help.
The advice for now is read read read read!

There are good articles on this sites links section and article section.
Read up on "cycling" your tank. Different filtration types etc and think about what you want to keep in the tank - BEFORE you buy it. That is the cheapest way to do things, otherwise you end up spending twice the money as you end up upgrading!
Standard setup = display tank with T5 lighting, plumbed to run into a sump below it divided into three chambers. First = skimmer, Second = Deep sand bed with a bit of cheatomorpha and cheap lighting, third = return to tank with a bit of live rock.
So, for that to make sense, read up on what a protein skimmer is, why you would want a deep sand bed, how chaetomorpha (a kind of macroalgae) helps, and what live rock is. Cant give a proper answer now as I'm in the middle of an exam... ;-P