So we just played our first game of Rebellion but there are some things that I had some questions on. This first play through was just us going through trying to learn the game. Thank you all in advance for your responses!

1) We had our first battle that was only air combat. Imperial wiped out my xwings in the first round of battle which left my leader on the planet with no ships. What happens to my leader after the battle has ended?

2) When my xwings were destroyed, I read in the rules that they are not destroyed right away but they have a chance to still attack. So after my xwings are attacked and destroyed I remove them off the board, finish out my counter attack, and then place them in back in the supply?

In case you didn't see my post on BGG:

1. I assume you're wondering if your leader is captured- he isn't. Leaders can only be captured via missions where it is specified that they are captured. However, pg. 12 of the Rules Reference does have an interesting note on rescuing captured leaders:

If there are no Imperial units in a captured leader’s system
(usually after an Imperial defeat in combat), the leader is
immediately rescued and moved to the base as normal

2. Think of a combat round like this ("Deals damage" includes playing damage cards):

Space Combat
1. Attackers deal damage
2. Defenders deal damage.
3. Damage blocks are applied.
4. Defeated figures are removed.

Ground Combat
1. Attackers deal damage
2. Defenders deal damage.
3. Damage blocks are applied.
4. Defeated figures are removed.

If neither side retreats, combat continues this cycle until one side is defeated. So, as you see, units are not removed until their round is over. So, the attacker does have a little bit of an advantage, but it's not as overwhelming as having the opportunity to remove enemy units before they're even allowed an attack.

Actually the defener blocks damage before the defender deals damage. This is important because a defender can't use a block card the turn it is drawn if it's drawn through the dice.

So it's

Attacker rolls dice
Attacker applies hits
defender plays blocks
defender rolls dice
Defender applies hits
attacker plays blocks

Same for ground and space battle no different.