In episode number 21 of naruto shippuden.
episode 71 they capture the 2nd tailed beast and episode 144 they capture the 6th tailed beast
there is more than one tailed beast that the akatsuki catches, you'd have to be more specific, however the 8 tails (killer b) and the 9 tails (naruto uzumaki) have not been caught by the akatsuki
The episode is called The Beast Within.
The jinchuuriki for the Yonbi (four-tailed beast) is Rōshi.
If I remember correctly the first tailed beast they collected was Gaara, the Shukaku. The first one they attempted to retrieve was Naruto, The nine-tailed demon fox, or Kyubi.
episode 71 they capture the 2nd tailed beast and episode 144 they capture the 6th tailed beast
Episode 796 the 7th beast apppears
Shippūden episode 121
Shippuden Episode 112
Naruto Shippuden episode 72: The Quietly Approaching Threat.
Naruto Shippuden Episode 99: Raging-Tailed Beast.
Episode 99 is about sealing the three tailed beast and creating a barrier over it
In episode 151 it was pain that defeted Sir Utakata.
the provent has 1000 tailed beast.
the two-tailed beast
in the condition itachi's in he'll probably lose but in tip top shape maybe there's hope for itachi who know.
Ichibi no Shukaku is gaara's tailed beast which is sealed in him