Not in the current version, at least not often.
Peaceful mode means that no monsters spawn, so there will be no Slimes.
You can find slimes in flat areas at lease 6-7 blocks wide. Or in slime dungeons.
i have been playing with the farming of slimes on xbox edition and i have came to conclusion that they always spawn at the same speed unless there is a light source that slows down or stops their spawning.
No. Because your world is different from everybody else's and therefore the website would not be able to find slimes in all of those worlds.
There are 3 sizes of slimes in Minecraft that naturally spawn. Big, Small, and Tiny.
there are magma cubes but no slimes.
The flat world seed spawns alot of slimes. But every seed spawn slimes.
In the bottom layers of the map or (if you have Weekly Snapshot 12w40a or above) in swamps.
Apparently yes. But the smallest slimes don't harm you, they don't deal damage.
No, not as of March 27th, 2013.
Slimes cannot spawn in the Nether in Minecraft. They are exclusive to the Overworld, where they spawn in specific biomes and under certain conditions, primarily in loaded chunks below Y-level 40. In the Nether, you would typically find different mobs and creatures, but slimes are not among them.
Slimes can, and awkwardly creepers can too.