I need and example for adding (semicolon) after each bookName in array of bookName , and change the last semicolon to (and) , What i have is {"me befor you","fallen","inferno"} what i need as a result is (me befor you , fallen and inferno)

Right, so this is really quite a simple thing to do (As I said in the comments):

books := []string{"title 1", "title 2", "title 3"}
list := fmt.Sprintf(
    "%s and %s",
    strings.Join(books[:len(books)-1], ", "), // join all elements with , excluding last one|
    books[len(books)-1], // last element in slice
)

Demo

How it works:

• strings.Join is part of the standard package strings, which does what your home-grown impode function does. No need to write it yourself
• books[:len(books)-1] "creates" a new slice containing all elements in the original slice, excluding the last one. Joining these elements with comma's is what you want. You just want an and bit between this and the last element in the slice.
• books[len(books)-1] gets the last element in the slice
• fmt.Sprintf("%s and %s": this creates a string where the first part is the comma separated list created by strings.Join, and the second part is the last element in the slice.

Together this yields "title 1, title 2 and title 3"