I've seen:
point blank
the getaway
dirty harry
bullit
bring me the head of alfredo garcia

what are some other great ones?

The French Connection
Mean Streets
The Godfather I & II (not sure if they are what you are looking for in terms of "crime" films)
Dog Day Afternoon

The Godfather 1 & 2. Forget about the third sequel.

I mean in terms of 70's explotation type films. The type of films guy ritchie and tarantino base their work on.

Across 110th Street
Charley Varrick
Rolling Thunder
The Outfit
Trick Baby
Mr. Majestyk
Get Carter
The Taking of Pelham 1,2,3

Some of those have played at Tarantino's festivals, so they're probably safe bets. I even spotted the "Pair of pliars and a blowtorch" line in Charley Varrick

check out
Death Wish (1974)
Point Blank (1967)

and blue underground has a great series of 70's Italian action flicks that is right up that alley
Revolver (1973)
How to Kill a Judge (1974)
Street Law (1974)
The Big Racket (1976)
The Heroin Busters (1977)
Contraband (1980)

and of course Sonny Chiba's The Bodyguard

also might check this out Who Do You Think Your Fooling?

You're Still Not Fooling Anybody

Fight For Your Life
Shaft
Super Fly
Willie Dynamite
The Gauntlet
Walking Tall
Walking Tall Part II
Walking Tall The Final Chapter
Midnight Express
Sugarland Express
Electra Glide In Blue
Gloria
Hardcore
Prime Cut
Serpico

I love those movies. And the third one in what I call the Walter Matthau Being Serious Trilogy, The Laughing Policeman.

The 70s were the best decade for gritty crime flicks. Today it's all about nauseous camera movement, explosions, and physically impossible action.

One of the quintessential crime flicks from the 70s is The Super Cops directed by Gordon Parks (Shaft). Unfortunately, it's not available on DVD yet.

http://www.imdb.com/title/tt0072228/

Coffy
Friday Foster
Foxy Brown
Dolemite

The Seven-Ups

Great cars chase scene.

You might try a couple that Tarantino released on his Rolling Thunder imprint:

Switchblade Sisters
Detroit 9000

SS has some camp elements (could be a plus or minus depending on your mindset), and the acting is pretty terrible, but it's well written and shot. I enjoyed it. D9000 is dead serious, and Alex Rocco is very good in the lead, but I didn't like it as well. It likewise is well shot and edited (notwithstanding a visible shotgun mic in a scene or two).

It's from the 60s, but I believe Tarantino was influenced by Tokyo Drifter and "borrowed" a couple of shots from it in Resevoir Dogs. Also from the 60s, Band of Outsiders made such an impression on him that he named his production company after it. Since you listed Point Blank, a 1967 film, in your OP, I don't feel it's inappropriate to recommend a couple of 1960s films

Le Cercle Rouge (1970)

french connection
serpico
pelham 1 2 3

That is one of the best.

Anybody seen this one?

thats a great trailer

Third sequel? how come nobody told me about this, I thought they only made two sequels?!

It's from 1968, but The Split with Jim Brown is very 70ish with a slight blaxplotation feel.

Can't emphasize this one enough. Don't be put off by the horrible remake, the original is a stone cold classic.

Also, Tarantino "borrows" a lot from Leone. Obviously not "70s crime", but worth noting...

Chinatown