You can try some of the more well known comics like Watchmen. An amazing work but maybe a bit heavy if you are a beginner in comics.

Other works you might enjoy include All Star Superman (as mentioned by another commenter) or Batman: The Long Halloween.

You should just browse the web (amazon.com for example), check out some stuff you might like and look at reviews. Just try something and find out what you like!
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I’ve been reading comics for quite some time

http://www.marveldirectory.com/

for instance: this is my favorite…
Real name: Norrin Radd
Occupation: Adventurer
Identity: Public
Legal status: Citizen of Zenn-La with no criminal record.
Place of birth: Zenn-La Group
Affiliation: Former member of the DEFENDERS
First appearance: FANTASTIC FOUR, Vol. 1 #48

History: Norrin Radd - former hearald of the mega-tyrant Galactus, offer his life to protect his native planet, placing him in the service of Galactus as a silver suited sentinal. As a galaxy cruising protector endowned with superhuman strength, he is able to control and direct cosmic energies, with enough force to destroy a city. After visiting Earth, the Surfer finally betrayed Galactus and refused to supply his world-devouring appetite. His punishement was confinement to earth - but he escaped and currently soars the starways as a universal protector.

Height: 6 ft. 4 in.
Weight: Unknown
Eyes: White
Hair: None

Known superhuman powers: The Silver Surfer can endow himself with Class 100 strength, enabling him to lift (press) over 100 tons. He possesses the Power Cosmic which he can use to generate powerful force blasts or to rearrange molecules. The Surfer travels on a "surfboard" which responds to his mental commands and is as indestructible as he is. He has a Cosmic Awareness which allows him to feel energy around him.
References :
http://www.adherents.com/lit/comics/comic_book_religion.html#Ca

One of my favourites of recent years is All-Star Superman (a 12 issue series). It harkens back to the days when gritty realism wasn’t as important as fun and a sense of hope and wonder.
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My suggestion is choose a category and stick with it. Don’t go out and buy every comic book that looks interesting, you’ll blow all your money and get nowhere.

Myself, I collect Spider-man. That means I collect the standard issues(Amazing Spider-man, 3 issues a month) along with the occasional limited series(usually 3- or 4-part stories), and whatever back issues I can get my hands on.

Other than that, limit yourself to the occasion limited series that looks interesting; don’t try to collect more than one or two regular series at a time.
References :

Jim, http://www.bible-reviews.com
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