I have seen in the loading screens the uchitgatana is a weapon that causes bleeding, but I have yet to find it. The dark souls wiki says Shiva sells it, but I haven't found Shiva. I have been invaded now twice by players weilding weapons that even when I block, cause bleeding. It is slightly irritating. Any idea where I can find a weapon that causes bleeding to even the playing field?

Don't all of the "curved sword" class of weapons cause bleeding?

@Devoid: I am not sure. I feel like I have upgraded a couple and they don't seem to be causing bleeding, but I could be wrong.

@TeamJersey: Hmm.. I may be wrong, that might have just been in Demon's Souls. A quick look at the wiki shows that only a handful of weapons cause it.

You can get an Uchigatana from joining the forest hunters covenant. You will meet a member at the bottom of blighttown, by the ramp up to the wheel-elevator thing (ground level). He sells all that crap.

The bleeding effect doesn't seem to work the same way as in Demon's Souls, it seems like every few hits you just do one attack that does a much larger amount of damage. I haven't gotten the "ticking" bleeding effect that deals damage over time.

You can get the morningstar from Firelink right from the start. It's a decent weapon that causes bleeding. To get the most out of it, you have to get successive hits in a row.

I know the mace and spiked club cause bleeding. I never used them though since I'm a halberd dude. I think some daggers do as well.

There's a Morning Star just outside of Firelink that has a 300 Bleed effect. 
 
I can also suggest running around The Depths as a Human - you may get invaded by NPC Black Knight Kirk who will drop a Barbed Longsword, it has 300 Bleed, which stays on the weapon even after adding an element - my copy is currently a Flaming Barbed Sword that inflicts Fire and Bleed.

Great Scythe is probably the best bleeding weapon.  High base damage, bleed damage, only weighs 5.   Upgrade that to lightning +5 and shit gets real, it's the weapon i'm using.
 
You find it in the catacombs.

The Bandit's Dagger that the thief start with, and that you can get as a rare drop from the rogues in Lower Undeadburg, does bleeding damage. It was pretty fun tearing up the thunder breathing drakes with it but it's kinda weak on things that don't bleed or can't be backstabbed so I killed the merchant.

@Marz: Gracias. I think that is what I am going to shoot for. How slow is it? How much str do you need to equip?

@TeamJersey: The merchant in Undead Burg drops the Uchitgatana, if you don't mind killing him.

@Marz: Gracias. I think that is what I am going to shoot for. How slow is it? How much str do you need to equip?

@Marz: I thought the bleed effect works best when stacked. The more hits = more bleeding. Think of the bandit's dagger. So, a faster weapon with bleed is more effective than a heavy hitter.

I know katanas do for sure. Can't tell you about anything else though. Sorry.

I know I've tried bleeding weapons, but have never noticed what effect they have on enemies. How do you know they've caused bleeding? Are there any visual cues to tell you it worked? Most of the time enemies just die with 1 to 3 hits so it seems like a waste of time. Is your only option to stare at their lifebar and hopefully see it go down gradually?

Also, are there any Toxin-based weapons (not just regular poison weapons) in the game, or do only enemies get those?

@mason: From what I have seen is that once you hit enough you do a bleed damage hit. I play as a thief, and I still use the Bandit's Knife. Upgraded to +10 though. Anyway, when hitting enemies with it I would do, let's say 10 damage each hit. Once the bleed damage effect has been stacked up or something you will suddenly do an attack which does 30 damage instead. Then you scale that up and see that you can do massive damage when the bleed goes off. Those numbers are completely wrong, but that seems to be how it works.

When you do the bleed damage the enemy will bleed more, and you get a slightly louder (or at least different) hit sound. A more... bloody sound in a way.

So no gradual bleeding I am afraid. As far as I know.

@Marz: I thought the bleed effect works best when stacked. The more hits = more bleeding. Think of the bandit's dagger. So, a faster weapon with bleed is more effective than a heavy hitter.

Kill the undead merchant, that's how I got mine.

@Durandir: Oh so bleed is not just another version of poison that drains HP. You're saying it makes successive hits more damaging? Guess I never thought of it that way. I'm playing a guy with high bleed resistance, so I've never really noticed what the effect does.

I may kill the undead merchant. I never purchase anything from him anymore. Thanks, guys.

@mason: Well, yes and no. I am not sure how you, the player character, is affected by bleeding, as I haven't had that happen to me myself. But this is how it seems to work when you inflict bleeding damage on enemies: You need to hit them several times for the bleed effect to happen. For me it has usually been three strikes with my Bandit's Knife, but it varies. Every hit adds to the enemies bleed bar (the same bar you get when you are about to be poisoned, cursed or get bleed damage yourself). On the hit that brings the bleed bar to the top, you will do more damage to the enemy. It appears to be a certain percentage of their health, but I have no idea about that. Once the bleed damage has been dealt, the bar must be filled again for it to happen once more.

So you can kinda view a weapon that has a bleed effect to be a weapon that crits occasionally.

Weapons that infect bleeding inflict a certain percentage of Bleeding on hit, in the same way Posion works. Once that bar is full the target is Bleeding and your next attack deals damage that is based on a percentage of the enemy's max health depending on the weapon.
 
This is can VERY strong against high vitality, tanky characters, although it is significantly less effective the lower someone's max health is.

bleeding weapons work as such , After X number of Hits , the bleed activates for Y% of the targets total health .. almost all curved blades do this ... im too tired to go through the strategy guide and tell you which specific weapons do what damage , but thats how the damage is applied

Bandit's Knife (and Jagged Ghost Blade) causes bleeding, I'm sure about it (because I use it all the time :P) and it's relatively easy to find it.