good website for comic reviews is
http://www.thefourthrail.com
At the mo, personally I'm sticking to trades (and the industry seems to be leaning in this direction as it attracts a larger fanbase this way- all the Marvel stuff is collected in trade form only a month or 2 after the final issue of the trade is finished. The DC stuff takes ages, but generally more and more are getting published). Another plus point is you can get most trades from amazon.
As to what comics, it really depends what you were into before- there's a huge variety of things out there, and it's hard to narrow things down without knowing your tastes.
Just to recap on a few of the better old ones (everyone likes different things though):
Astro City (though there has been a recent mini)
Batman: The Dark Knight Returns
Batman: Year One
Daredevil (Miller's run- collected in Daredevil visionaries 2-3, Man without fear, Born Again)
Preacher
Sandman
Swamp Thing
Superman for all seasons
V for Vendetta
Watchmen
X-men (Byrne and Claremont run- collected in B&W in x-men essentials vols 2-3)
Recently, there's been a number of decent comics. The Vertigo line in particular has been impressive, with the following:
Lucifer (sandman spinoff)
Fables : In Fabletown, fairy tale legends live alongside regular New Yorkers. It's a good construct with which to tell a story
Y-the Last man (every teenage boy's dreamt of this, but what would REALLY happen to the last man on Earth)
Other stuff that I'd have a look at includes:
Current run on the main Batman title
Gotham Central
Powers
Queen and Country (modern day espionage)
Sleeper (undercover agents, double dealing etc- out of the current titles, this one's one of the strongest)
Ultimate Spiderman
Ultimates (avengers reimagined)
There's more, butI'm getting tired of typing without knowing what your tastes are
