"And where is the fork?"
Translation:А где вилка?
Yes. They are used in slightly different situations.
1) For connecting words e.g. "a cat and a dog", "mom and dad" etc. you can only use и: кот и собака, мама и папа.
2) When connecting sentences in Russian you would have two cases:
The statements are the same, similar or related. E.g. I like coffee and he likes coffee as well. Use и in this case: Я люблю кофе, и он тоже любит кофе. И = and in the sense of as well.
The statements are opposite or different. E.g. I like coffee and he likes tea. Use а in this case: Я люблю кофе, а он любит чай. А = and with a flavour of but :D
In this particular example "А где же вилка?" it's not one of the cases above. "А" is not connecting anything, words or sentences, it's only emphasizes the question as if it was connected to some previous context. Remember, "а" is connecting different or opposite facts? "[Ложка здесь], а где же вилка?!" = [The spoon is here], and where is the fork?
"А" gives you the feeling that the fork not being there is either wrong, or different from the situation with all the other kitchenware or so :D
Sorry for the long answer ^^