いや、どうしたじゃねぇよ!お前が良いイチゴが出来たから、買ってくれって言ってきたんだろうが!
Let's break it down:
いや、どうしたじゃねぇよ!
Here he is saying that it's not right to say "どうした". The exact meaning of どうした here can change but you say you have no problems with this part so there's not much point in elaborating on that.
お前が良いイチゴが出来たから
You confused a て form type of から with the regular cause-and-effect meaning of から。When から is used with the て form of a verb, the meaning is more explicitly temporal and roughly translates to "after/once/". In this case since the past form of 出来る is used, から just means "because/since". So this changes it to:
Because you managed to grow good strawberries...
Next:
買ってくれって言ってきたんだろうが!
This one is a bit more tricky. Let's break it down slightly further:
買ってくれ
This is just a very colloquial way of asking someone to buy something, and:
って言ってきたんだろうが
The って here is the more slangy version of the と particle, so he's quoting "買ってくれ". 言ってきた means something along the lines of "you were[over time] saying"(in a different sense than ていった). Together with だろうが(emphasis, "didn't you?!") this entire clause becomes:
You were asking [someone] to buy didn't you?!
Bringing it all together a bit more freely:
Don't "what's going on" me! Since you managed to grow good
strawberries, you were asking [people/me/context] to buy them
didn't you?!
To be honest the very first part could be different depending on the exact context but this is a very likely option.
だろうが
てくる/いく