i need help with mages guild supsenion

[that spy was a cow]

where can i find the plants?

[King Nerevar]

Which plants? For me, they where always others.

Edit: I found this.

First Offense
If your crime was a theft, you need to acquire 20 Dragon's Tongues and 20 Redwort Flowers. For murder, you need to acquire 20 Vampire Dusts and 20 Daedra Hearts. On your first offense, there is actually a glitch that allows you to collect 20 of just one of the two required items, although you will lose whatever you have collected so far of the second required item. Once you have collected enough, return to Raminus Polus to turn in your ingredients and be reinstated.
Full details on where to find each of the ingredients are provided on the individual ingredient pages. The following list provides only a couple possible suggestions.
Dragon's Tongues
21 plants are near the entrance to Fort Redwater.
Enough flowers are scattered south of Bravil to cover the 20 needed. Look along the path and on the north shore of the inlet to the Lower Niben.
6 plants are on the shore of a swamp that is located just above the 'd' in 'Blackwood' on the map
14 plants can be found just southwest of the entrance to Fort Irony.
Redwort Flowers
Alchemy stores may randomly stock them, but you will probably have to wait for enough to spawn.
21 plants are on the shore of a swamp that is located just above the 'd' in 'Blackwood' on the map (these are easiest to find if you have installed the Knights of the Nine plugin; then there are 25 at the entrance to Fort Bulwark). There are also 11 Dragon's Tongue plants here.
Daedra Hearts
Starting at level 12, alchemy stores may randomly stock them, but you will probably have to wait for enough to spawn.
Dremora are easiest to find before you have completed the Main Quest, or just check near or inside any Oblivion Gates.
Brittlerock Cave and Conjurer Dungeons are other locations where hearts may be acquired.
Vampire Dust
Raminus will only accept standard Vampire Dust (not the rare Vampire Dust found on Bloodcrust Vampires).
Never sold in alchemy stores.
Vampires can be found in various Vampire Dungeons.